I would be very surprised to find more than 20% of Proton Mail users sharing this viewpoint.
I think that the strongarming is a result of them actively trying to target the layman, them not wanting complaints from newbie users who lose their password. Not that that justifies it of course.
I thought about this, but no, that would fully compromise the data stored in both accounts. This is because the new recovery message would be intercepted by Proton, relayed to the attacker, and then it's game over, first for the first account, and then similarly for the second account. The encryption of Proton applies only to historical messages.