Security is constantly used as a guise for removing consumer rights and as someone who has been in the security industry for about 9 years I'm so sick of it.
First and foremost, everyone please understand: the user should be allowed to opt into your concept of insecurity: you do not know their threat model and you do not know their risk tolerance.
Using exploits in low level drivers in the wild is approaching APT level, and even if there were a simple one to use it'd likely be useless without some sort or local access to the device (bar some horror show bug in a Bluetooth or WiFi firmware). The risk is incredibly low for the average person. I'd put it pretty close to 0.
Wire transfers aren't instant and for large sums (your inheritance) the banks will likely require more than just a request from your app. If the bank cares about that then they can also use the attestation APIs which would be more than sufficient, as much as I hate them.
This boogey man of the APT going after my technologically illiterate with nation state level exploits needs to die. Long ago we entered a new era of security where it just isn't worth it to waste exploits. Especially when you can just text people and ask for their money and that works plenty well.
Security is not a valid reason to soft brick consumer devices at some arbitrary end of life date.
It's interesting what people expect of Proton Mail. I've used it for a long time but for only one reason really: their revenue stream is my subscription and not ads. I've never even given a second thought to all their encryption claims. Even with Proton Mail if I ever wanted to send a "secret" email I'd wrap the content in my own personal keys.
With respect to IP addresses of email logins, I'm surprised they ever claimed they don't have logs. You've always been able to review the IP of a login through the web UI as far as I remember. Was the idea that that was also supposed to be encrypted?
Personally I'm OK with them complying with court orders, but I understand that "the definition of criminal is state defined" and that poses serious issues. It kinda seems like if you want to do something that could be considered criminal at some point in your life by your country you should consider something other than a 3rd party email provider for those messages. Signal would be a step up in that regard if you still wanted to use a third party.