What's wrong with optional typing? All it does is formalise docstrings into an integrated syntax.
And "optional" is a misnomer unless you only ever touch your own code. Programming is generally a social activity, so for most of us, "optional" means just means "inconsistently required".
I don't have a philosophical objection to typing, but I'm yet to see a syntax that won't muddy Python's.
Optionally means that it's not required or mandatory.
You don't need to use it if you don't want to. If you're working on a project and the project follows a style guide then you follow the style guide, but nothing forces your bosses to require it. The code will run anyway.
Your bosses aren't forced to use it. This means that if they don't want to use them and they don't believe the official style guide has to impose them, you don't have to use them.
If your bosses decide to impose them and change teh official style guide to require type annotation then your personal taste doesn't have any say in the subject either way, and you only need to act like a professional and be a team player.
But the key issue is that no one is forced to use optional features unless they really want to.
People will start using and it will become mandatory at some point
"Dynamically typed Python variables considered harmful"