These are concerns that will arise in some organisations, for sure. Personally, I don't have a need to work together with people who cannot be bothered to learn

These are concerns that will arise in some organisations, for sure. Personally, I don't have a need to work together with people who cannot be bothered to learn TypeScript. A nice type system is something you really want, and which improves code quality. No need not also to use linters and unit tests. These things do not oppose each other, they work together nicely.