Hi, trans person here. I often describe my life before beginning to transition as an act or a job I had to perform, but wasn't really me. Anything I did in my old role was done by me, not the character.
In Elliot's case, he was a dude playing a dudette, dressed up as another dudette. Whatever performance was happening on or off camera doesn't ultimately change who the person actually is.
That's very logical and easy to understand. Personally I wouldn't be upset if I was Elliott, but there are many trans people who have a strong aversion to hearing their old name. Again, comes down to the audience, but a lot of folks would say something like, "before he transitioned", rather than mentioning the old name.
Hope I don't sound too nitpicky, just wanted to say it in case it helps.