Because it's been forced into many of us as if it were the holy grail, which I don't find is the case. I don't make many of the mistakes that are sold as gotchas of why to use TS when I program in JS, and I've maintained systems which have millions of daily active users.
I'm also told sometimes that it would help other (more mediocre) developers, but in fact many of those developers end up using any often, or simply the wrong cases because, well, they are mediocre in the first place (I'm a bit harsh on them, I know). It's not that I am not a fan of typed languages, C/C++ being two of my favorite ways to code (btw the auto syntax was a game changer for me).
As an example, we had a nasty situation where the TS transpiled code would force every "import" into require, to the point that the recommended way by the package (chatgpt) was to create an eval'ed function:
new Function('modulePath', 'return import(modulePath)')")
It's kind of like our PMs for both gigs keep nagging us to use chatGPT for everything, and pushing us to start using Github Co-pilot (tldr; some sort of chat gpt for code review or something). I used to not hate chatGPT but I quite hate it now (one of our startups is drumroll... building on top of it).
For libraries, TS definitely makes sense. But 99% of the time most of us are not programming reusable libraries.