Yes, in a good dev workflow mypy errors will not pass basic CI tests to get merged. Types are not really a problem in modern Python workflows, you can basically have a better type checker than Java out of the box (which can be improved with static analysis tools). The biggest problem with Python remains performance.
That's actually a good idea, enforcing it. Still, do these linters protect against misuse? E.g I have an int but place a string on it somewhere?
Yes, in a good dev workflow mypy errors will not pass basic CI tests to get merged. Types are not really a problem in modern Python workflows, you can basically have a better type checker than Java out of the box (which can be improved with static analysis tools). The biggest problem with Python remains performance.