To me its very powerful to have the same developers do both front end and back end. With modern frameworks its probably easier for front end devs to do back end

To me its very powerful to have the same developers do both front end and back end. With modern frameworks its probably easier for front end devs to do back end work than Rust/Go/Elixir devs to dirty themselves with JS. So even though ts is suboptimal it allows one language, one set of tools and developers.