The only reason I haven't cancelled yet is because I moved my family, including my parents, onto a family plan with them, and that's going to be a lot of work to move everyone again.
But this shit fucking sucks. I recommended this product to my loved ones because it's supposed to be trustworthy and secure, and now I find out it's neither of those things.
If you're a Proton customer right now and not in a position to simply cancel your account, submit a support ticket laying out your concerns. I got a detailed and lengthy response back within a day (one that was clearly not a form letter either, it directly addressed all the points I raised). Flooding their support channels will make it clear that they are in some serious shit here.
Write to the Proton Foundation too. Demand that Yen be removed from the board and the company, and that serious changes be made to the leadership at Proton to ensure this never happens again.