The truth of the matter is, we is entities on earth believe of something which we only believe to be true, because that is the way our brains are programmed from an early age!
We are programmed to speak, to think, to talk, to see & hear, the way others want us to & human beings are mimics are similar to that of chameleons in some ways, which blend into surroundings
But in the case of humanity, we are on a higher plane of existence, we also have individual thought, although our thought process is manipulated & those who seek to control us!
Therefore the existence in which we live, is a higher level of thought & manipulation & we believe in what we are told to believe in.
When you also consider that we have people in each country who have got weapons, to make the people do exactly what they want us to do, if we fail to comply with what it is which is in their missguided agenda.
We would be killed.
In someway we are just like drones, but we are allowed to live lives under their control, we can have houses & cars & holidays, bank accounts with money, everything that we believe is available to us.
But anyone with a good education knows that everything that is available to us, is not available to us!
Another mitigating circumstance to our situation, is the lack of cohesion between nations, until we become a United Earth we cannot move beyond petty things, in some ways we are kept in the here & now moving forward very slowly, probably 1000 times slower than what we could be.
You may be asking what relevance this has to your question, the truth is it also goes to that these programs we watch on TV, fantasy, an escape from reality, but the storylines, are manipulated, just as human life is manipulated, just as thought is manipulated, everything is a manipulation!
All the people that rule the countries are millionaires or billionaires, but these people are so consumed with fame wealth & anything but uniting all the nations of the world to become one species.
So that we can start to put our technology together & begin our true purpose, the seven deadly sins coming to play whether you believe in god or not, the ideology of the seven deadly sins is a perfect analogy for these people, who rule us, sloth, wrath, greed, gluttony, envy, vanity, 7th escapes me at the minute!
But the point being is that these people who rule us cannot rule us sufficiently because the to greedy.
One day on our Earth there will be a person similar to that of William Wallace or someone like him who will lead humanity into salvation from the tyranny that we face under the hands of the government's that rule us now!
In reality the storyline to Star Trek Voyager is irrelevant to the greater picture.
Gene Roddenberry was an extremely intelligent man, all the people involved within Star Trek, Voyager, Deep Space Nine & all the other great film series which came from the writers & Gene Roddenberry.
The only thing that humanity has to hold onto in truth, is it's individuality, its ability to be able to learn, expand its knowledge, on its own without the assistance of the government's, & that sporadically through science & technology now, art commerce music & all the things that came before, which will be our legacy, & although our governments don't see humanity as a team, instead cause religious racial & sexual tension in discrimination, take money from people in insurance if they become sick or unwell, they abandon them,. They're not even willing, to help the damaged drones, because they know they have billions more to take your place!
When they don't have enough workforce in the nation that you live in, they will just import them from another nation, because they are all working together whether you believe it or not, so that they live a lovely life, go on holidays, have all the best of everything, all at the expense of the denial of a future or furtherment of humanity & of our race!
Even people in wheelchairs have purpose, people with mental health have purpose, but you've got so many corporate entities who also seek to undermine human for personal profit that our battle has only just begun!
Banking, pharmaceutical companies, any company that wants to make profit because they put profit over progress.
Hopefully one day we will get people in power who will see the benefit of uniting all the nations together as one letting people go where they want to go, as long as they give so many hours a week of work as a reward they should be allowed to do whatever it is they wish to do, in their free time.
The problem is the replacement of money, because in Star Trek there is no money, all medicine is free, the ideology of Gene Roddenberry, is not just a story, it's an ideology, but if we put into practice, we would evolve as a species, medicine, technology, science, everything, we'd just go into overdrive!
But people think that owning a stupid little house or a stupid little car car & having a wage is more important than building buildings & architecture & the civilisation where they put the advancement of the human race before their own needs!
Sometimes people need to be led, sometimes people need to follow, & sometimes people need to lead! But unfortunately for us, we all willing to follow, but we don't have one person in power who truly wants to lead!
Or even a United Nations of Earth that want to lead the world as a council of Nations deciding on the progress of humanity because they have their own selfish greed and needs!
I really don't care about material things! Although I do have material things, but my mother would tell you you I would give up everything I own to live a life where we become like the people on Star Trek the ideology that we have rulers of all the nations of Earth coming together sharing our technology & medicines or science, everything to make our species better so that we can travel the stars & our reward would be knowledge & understanding of the universe that we live in, to be part of that would be a dream come true for me!
It should also be a dream for every other person on this planet because you're all forgetting that one day this planet will supernova & blow up, then where will you manually be?
Do you care so little for your children or your children's, children's, children's, children or your legacy of children, that you would put your own personal ambition ahead of your future generations?
I know that I will be dead long before for humanity ever comes together as one!
Enough for this film is like a layer cake, different layers of the cake with different flavours, something looks the same but it doesn't taste the same, any story can be manipulated into the way the Gene Roddenberry wanted people to believe it, because his ethos was good primarily for his moment in history, it may have come from a dream that one day this is how we would exist.
But for the here & now he wanted to give you an escape from reality & the hardness & hardships of life!
My answer to your question is exactly what you said yourself in the storyline they forgot who they were & they believed that they really were the Voyager crew, they also adapted just as we adapt & evolve as human beings, particularly if you believe in humanity coming from apes?
Why not believe that they evolved to a point of believing their own illusions, if you wanted my personal opinion?
Here it is:
I would say that when Harry Kim fell into the liquid of silver, which was not a sentient lifeform, a sentient life form was born,
In reality Voyager didn't just leave the planet & all the clones behind, they left behind children & they may have been children with the memories of all the people that they cloned, but regardless they were children nevertheless!
When you consider that, you should also consider how many human beings on this planet who are in there are 30, 40, 50, 60, 70's can you remember anything before the age of 5?
In time people forget certain things, it's called irrelevant information, because your brain although so very vast & superior, only had enough space within it to store a certain amount of information, so the make-up & chemistry of your brain, is to keep important information, & expel irrelevant information, that is why you cannot remember every day of your life before you were 5!
I think that explanation would explain.