A lot may have been simply my own inexpertise in Scala. But I remember it being much more of a fight, and subject to much more nuanced errors, to do anything interesting with generics or any more advanced typing. I would often stop, whereas at the same point in Typescript, I can just cast, and then see what actually happens at runtime. If I fail to be creative enough with my types, so long as I satisfy the type contract at some level, I can be wild wild west in the internals.

I do miss the for comprehensions, but have built an abstraction that does the same thing for my purposes. It isn't quite as good, due to the whole monad thing, and me fitting it to the average Javascript programmer who won't want to learn functional programming all at once. So at its core it is pretty much async/await with sugar.

I quite enjoy exploiting structural typing for unit testing purposes. Gone is the need to learn a mock framework and its DSL; just write plain ol' JS for the parts you are interested in, and tell the compiler to chill. ;) Long term, of course, you should probably just have doubles.