Likely the reason is that you really only need just mypy. It handles the type issues. Pylint is useful, but doesn't really overlap with mypy in terms of what it catches, and there's no need to use pyright or to write type-verifying unit tests, or to do runtime type validation if you have mypy.
Using mypy gives you the type safety equivalent of a compiled language. If you're using mypy, you don't need any additional validation that you wouldn't use in java or c++. I didn't downvote you, but the needless defense in depth is weird.
“Using mypy gives you the type safety if a compiled language” is far from the truth. Each tool has things that they don’t catch, or things that they sometimes false alert on.
Yeah mypy will get you maybe 90% of the way there, but the swiss cheese approach of stacking a few tools, even though there are redundancies, helps plug almost all of the holes.
People can argue about unit tests all day, but there’s very little cost to stacking multiple static analysis tools.
Using mypy gives you the type safety equivalent of a compiled language. If you're using mypy, you don't need any additional validation that you wouldn't use in java or c++. I didn't downvote you, but the needless defense in depth is weird.