I don't think it's a ridiculous idea? Children these days – I'd assume – need an email address at an increasingly younger age. So you pay $1 to get an indefinite voucher for that address – which might actually be worthwhile to some if their child's name is somewhat common and the full name is available today without a bullshit string of numbers at the end.

Granted there's no guarantee Proton will be around in e.g. 8 years, but so far, they seem to be doing reasonably well, and $1 is, like, the price of an apple.