In HP universe all the Wizarding community (apart from a few people) feared using the name Voldemort when referring to The Dark Lord. I wonder if the fear would persist after the death of Voldemort.
In Harry Potter and the Cursed Child, set (on the whole) at least nineteen years after the death of Voldemort, we see many people using his name freely:
- Rose Granger-Weasley uses his name, though of course her parents would have raised her not to be afraid of it:
ROSE: The rumor is that he’s Voldemort’s son, Albus.
So does Amos Diggory:
AMOS: Voldemort wanted you! Not my son! You told me yourself, the words he said were, “Kill the spare.” The spare. My son, my beautiful son, was a spare.
Some random person named Karl Jenkins does as well:
KARL JENKINS: Leave him and Voldemort’s child to it, I say.
As does Scorpius Malfoy, which is particularly notable since his family, as Death Eaters, had been calling Voldemort "the Dark Lord" for a rather long time:
SCORPIUS: And now you’ve found me. Ta-da! I was hardly hiding. You know how I like to — get on early. Stops people staring. Shouting. Writing “son of Voldemort” on my trunk. That one never gets old. She really doesn’t like me, does she?
Even Draco Malfoy, who was terrified of Voldemort, gets in on the fun:
DRACO: Voldemort is dead, Voldemort is gone.
With such a diverse range of people using Voldemort's name, we can assume it was in common currency.
There is no Canon answer regarding this question, but I will try to put down a logical answer.
After the First Wizarding War, when He-Who-Must-Not-Be-Named disappeared at Godric Hallow.(thought to be dead by his own curse rebounding) People just didn't start using his name openly, they still didn't call him by his name even though he is thought to be dead or just living somewhere powerless.
“No, thank you,” said Professor McGonagall coldly, as though she didn’t think this was the moment for lemon drops. “As I say, even if You-Know-Who has gone —”.
“My dear Professor, surely a sensible person like yourself can call him by his name? All this ‘You-Know-Who’ nonsense — for eleven years I have been trying to persuade people to call him by his proper name: Voldemort.” Professor McGonagall flinched, but Dumbledore, who was unsticking two s drops, seemed not to notice. “It all gets so confusing if we keep saying ‘You-Know-Who.’ I have never seen any reason to be frightened of saying Voldemort’s name.
-Harry Potter and the Sorcerer's Stone, Chapter 1
“He sat down, stared into the fire for a few seconds, and then said,
“It begins, I suppose, with — with a person called — but it’s incredible yeh don’t know his name, everyone in our world knows —”
“Well — I don’ like sayin’ the name if I can help it. No one does.” “Why not?”
“Gulpin’ gargoyles, Harry, people are still scared. Blimey, this is difficult. See, there was this wizard who went ...bad. As bad as you could go. Worse. Worse than worse. His name was...” Hagrid gulped, but no words came out.
“Could you write it down?” Harry suggested.
“Nah — can’t spell it. All right — Voldemort. ” Hagrid shuddered. “Don’ make me say it again.”
-Harry Potter and the Sorcerers stone, Chapter 4
So we can say that the Wizards possibly might not have called You-Know-Who with his original name even after the Second Wizarding war.
If I'm not mistaking, the majority of characters started referring to him by name in book 7 which lead to the discovery of the Taboo curse (being able to ascertain one's location when they speak a keyword, in this case 'Voldemort'.
As the 7th book progresses, fear of Voldemort wains and people start calling him by his name.