onboarding 10 Typescript Backend developers is like onboarding 10 developers from entirely different languages. Some are _heavily_ OOP driven, and turn literally everything into a class. Some are heavy on functional programming and start using curried functions everywhere. Others are used to classic express servers, while another group has only ever worked with graphql/prisma, or has only deployed on lambda functions and hasn't really seen express-based routing.

Literally everyone comes with their own project setting, they all have to get used to that specific folder structure, or those eslint/prettier settings. And on top of error-handling in JS/TS is miles behind Go's (and that's despite Go's error handling also being clunky and not as elegant as Rust's or ocaml's, but still much much better than JS's). It is _extremely_ easy to mess up a typescript project, it's significantly harder to mess up a go project (although obviously still easily possible :)

Btw. I also don't hate typescript/JS, I think it's a great language that allows for a big variety of expressiveness in entirely different programming domains, I personally use it all the time and enjoy it. I just don't think it's a particularly great language to scale a team with.