Bad arguments. I also won’t buy a Tesla just because good people work there.
I think you have fallen to the sunk cost fallacy as in you have recommended it to so many people that now you can’t move away.
If the product isn’t any good, the money is flowing to a dickhead and people are let go anyway (if they don’t replace themselves with AI), then there is no valid reason to keep paying for this product.
Also it’s a swiss company, which is problematic for so many reasons.

Well yes. Random people generating pull requests that they have no idea about IS different from a Tuta employee asking a Chatbot how to solve a specific problem.

Relevant Statement from Tuta on AI Code (and other stuff):
https://www.reddit.com/r/tutanota/comments/1ximsy2/comment/19ru7p9lepl34/

Doch!