...and then it just works. Everything works. You found every place, fixed every place; you've refactored the universe and it was so easy you barely noticed and start complaining about how long it takes to type in the changes.

With Python, chances are you didn't add type hints everywhere because you were moving fast, and likely enough the hints couldn't have been precise enough anyway, so now you have a long tail of increasingly less-often-hit bugs that you hit at runtime.

With Python you code fast, but you don't change existing interfaces fast unless you have a mindbogglingly complete set of unit tests. You can rip everything out and rewrite from scratch fast.

Rust is hard to learn, though, and it does require a lot of you even once you've learned it. "I demand that you think through carefully how to make this thing you want to do structurally safe" is a pretty high bar. Unfortunately, you always had to do this, or there were bugs. So the biggest tradeoff is really just: code fast with bugs, or code slow and correctly (with a huge amount of compiler help)? Sometimes fast + bugs is the way to go.