Different people use different words about their transition, and I think you’re imposing your own experience onto others.

If a gender diverse person tells me that their gender changed, then their gender changed.

If a cis person is assuming that a person’s gender has changed just because they transitioned, I’m going to correct them, because when held in ignorance, that’s a position that is generally based on harmful ideas about the trans experience. And if they’re interested in discussing it further, we can have a discussion of the nuance of how it all works.

Letting a cis person assume that all trans people’s gender changes when they transition does more harm than good IMO.

But to say that the only way for trans people to be is the way you perceive them to be

I am quite explicitly not saying this. If your gender changed, it changed :)