@sun just so you know, typescript at dayjob put me on a half-year sick leave in 2020 or so, and I still haven't fully recovered from it.

Partially because of how shit TS is, partially because of colleagues telling me shit like "we have to use because we have to use it". The all-time low was me asking for help from the guy who introduced TS to codebase and he replied with "i'm not a TS expect actually".

I delved VERY deep into it, tried to write good types, and all I got are:
- several consequtive mental breakdowns
- million "YourType is not compatible with YourType" errors
- hunderds of thousands of undecipherable error messages
- thousands "types are actually wrong" instances.

All in a codebase that isn't full of HJ-branded JS magic. In codebase that previously used flowtypes (which were also wrong).