The authors trick you with reasonable examples on https://www.typescriptlang.org, but in the wild, you have these ridiculous codebases that couldn't control themselves and they have this insane ratio of multiple declaration files to actual source files and you have to ask yourself, "Are you writing software to get something actually done, or do you just like write type definitions?"
Even people who write in C++ don't go to the lengths that TypeScript users do. It's super weird and cult-like.
There are some type libraries that parse GraphQL queries and CSS selectors. They’re crazy to look at but they’re hugely helpful.
And I would wager the bugs and jank are in no small part due to the extremely complex generics/constraints.