What sort of errors are you running into, and what project setup are you using?
If you're using Create-React-App-TS, that's a separate fork of CRA 1.x that adds TS support, and has _horribly_ restrictive lint rules (many common style practices are treated as _compile_ errors). See https://github.com/wmonk/create-react-app-typescript/issues/... for discussion. (I ran across this while trying to set up a TS project for another team.)
I'm happy to see the TS support in CRA 2.x, because now I can actually recommend that people use it to get started with TS support.
I personally had never actually _used_ TS at all until this last week, when I was helping that same team rework some of their code. They'd been slapping `someVar : any` across the entire codebase just to make the compiler shut up. I tried adding a type representing their API response object, added it as a prop to the appropriate React component, and showed them how you could start getting autocomplete and compile-time catching of mistakes, and suddenly they began to see that there were actually benefits of using TS, not just overhead. I'm hoping to try adding TS support in to my own team's codebase in the near future.
In that _specific_ example, I think the key part is the "... is not assignable to ServerRoute | ServerRoute[]". It's just giving you all the fields in the type of the object you _are_ returning, and trying to tell you "I can't go from an A to a B". But yes, hard to pick out the key bits of info in there.
If you're using Create-React-App-TS, that's a separate fork of CRA 1.x that adds TS support, and has _horribly_ restrictive lint rules (many common style practices are treated as _compile_ errors). See https://github.com/wmonk/create-react-app-typescript/issues/... for discussion. (I ran across this while trying to set up a TS project for another team.)
I'm happy to see the TS support in CRA 2.x, because now I can actually recommend that people use it to get started with TS support.
I personally had never actually _used_ TS at all until this last week, when I was helping that same team rework some of their code. They'd been slapping `someVar : any` across the entire codebase just to make the compiler shut up. I tried adding a type representing their API response object, added it as a prop to the appropriate React component, and showed them how you could start getting autocomplete and compile-time catching of mistakes, and suddenly they began to see that there were actually benefits of using TS, not just overhead. I'm hoping to try adding TS support in to my own team's codebase in the near future.