Holy crap
... there's a lot of bollocks talked about passwords.
My bank, and my main email account, are both pretty important to me. On those, I use strong passwords that are not reused from anywhere else. If I thought for one moment that my bank or my email provider was broadcasting my password, however encrypted, to every other internet service in the world, I'd close the accounts faster than you can say "formal complaint". I would deeply resent the idea that my bank had even tried to identify my email username, let alone password, or vice versa.
At the other end of the scale, there's dozens of tinpot little blogs (El Reg, I'm looking at you) that require me to log into something to post on them, and don't allow OAuth because... I dunno, they want to sell password managers or something. On those I see no reason not to reuse passwords, and I'll deeply resent anyone who tries to prevent me from doing so.
So this proposal is calculated to piss me off in two entirely separate ways.