Let's start with a clarification: Starlight "plan" was never about "Equality" - notice how she never gave away her Cutie Mark for example.
Starlight resentment against Cutie Marks and the "individuality" they represent is born from her own past - she had a friend in Sunburn and she "lost" him. In her mind, Sunburst getting his Mark and going to magic school is what stole him from her.
Therefore, Starlight's objective isn't found in "Equality" as a way to make everyone equal. The "Equality" is just a tool for erher real aim to remove the cause of her lost - in her view the Cutie Mark representrepresents the "ambition/vision" of a pony and that vision is what drives a pony to pursue his dreams even if that dream means to leave a friend behind... to leave her. AsSo the best way to be sure that she never has to say farewell again is to be sure that nopony ever has a reason to do something new... after all as she says in her song "You can't have a nightmare if you never dream".
Also worth noticing is that Starlight plan is not about "Equality" as in "everyone is equal and has the same rights" - that is not even the meaning of "Equality" she has in mind. The story isn't either a retelling of Animal Farm nor - despite what many seems to believe - an attempt at analyzing ideas related to real-world Communism. A better comparison would be Kurt Vonnegut's short story Harrison Bergeron ([full text available here, link taken from Wikipedia) - a dystopian story about people wearing external handicap devices to strip them from anything that made them different. "Equality" here means just that. Everypony need to conform to a common idea so that no one will try something that could disrupt status-quo.
Her desire is the same that moved Lum in the anime movie "Beautiful Dreamer": "I just want to be forever with my friends. Everyone else could as well not exist". For this reason the story also isn't a story about people realizing that they could be more happy if Social inequality was abolished: those are just Starlight claims to try to sugar coat what is really happening.
Under Starlight facade the reality is different. Ponies are unhappy, force coerced into an idea of abandoning their dreams so that no one will ever get away again. You see forced smiles during the "Our Town" song, you see desperate attempts to comb their mane in a different way being immediately stopped... you even see a prison used to subdue ponies into giving up to the "Equality" fake ideal. What Starlight is trying to achieve is not Equality. Starlight wants an Immovable Eternity, unperturbed by any dream or exception that may take anyone on a different path, a path that would take them far away just like Sunburst. Her world must be a static one, one where nothing changes - only then she may be sure that she will never have to say farewell again.
It should then be clear by now that the map isn't sending the ponies on a mission to fight against the idea of Equality. The Mane Six are sent there to help the suffering ponies that live under Starlight decree. And to help Starlight - a pony that raised a wall around herself in a desperate attempt to never have to suffer a loss again.