Typescript is a bolt on. It's purpose is to increase Microsoft's influence. Node's move actually trivializes Typescript by saying "Don't even worry about it. We'll strip it out."

And I've actually said to my teams before "High-level languages exist to make code better to read, not execute." Maintainability is as important as any other concern.

As for using Python or Ruby instead of Node, Python is always a fine choice. As a builder, always use your sharpest knife to cut stuff and your hardest hammer to nail stuff (my best backend tool happens to be JavaScript). But as a leader there is a real, quantifiable value to having a single language across your stack.

1. Less cognitive load.

2. Why pay two mediocre salaries when you can pay one competitive salary?

3. Full-stack JS devs are way more available than full-stack JS/Python devs.