Why does it seem like all this age-restriction and the consequential VPN bans are happening across the west all at once?

Britain, Australia, and Canada love massive government overreach for some reason. America seems to have escaped it by having a culture of just hating government in general.

I will say the EUs love affair with it is somewhat new (last 10-15 years or so).

Political/issue opportunism. One so-called "democracy" implementing one civilian-harmful garbage policy makes it that much easier for another to emulate it.

Guaranteed this is the next move they'll try in Australia too.