You would be surprised. I know of several trans people who transitioned and had surgery decades ago and don't tell anyone. Not even therapists or close friends. If you didn't know them before or have an important specific reason it needs to be known it just never comes up.
That was the goal for a lot of people until recent times. Even now there are still a ton of people who just do it and want to move on with their lives forgetting about it like an old medical issue they resolved.
You are mostly going to notice people who are early on or very open about it. One of the reasons that trans healthcare at a younger age is important is because it makes it much easier to blend in with society the rest of their lives. Blocking this care is going to make trans people more visible than if they weren't forced to go through an unwanted puberty.
Another thing is that a lot of people who have transitioned don't care about stuff like makeup or clothes. It's about identity and physical body features. That stuff comes secondary and early on is often explored more because it's new and can be validating. It's also not about orientation either, there are people who transitioned MTF living lives as lesbians and people FTM lived as gay couples. You yourself are an example of how the clothes you like to wear is unrelated to your gender identity.
For him it's not so much a worry about losing people as it is a personal branding ego thing. He's payed off people for stuff that was already known and his supporters didn't care about just to not mention again.