The main problem with TS is that your types are compile-time. You can have 0 uses of any/unknown, but you can still stuff a number into a string at runtime without any issues until it blows up.

I know you should have defined validators for every single external API, library and database, but at some level it feels silly to do all of this extra work.

Of course, but that comes with the territory. I just think it's really impressive how far TS has come, and doesn't feel like an "awkward patch over javascript" at all these days.

In new projects, I've found that it's now very rare to come across a library that doesn't provide typings, or violates the interface.