It wouldn't happen at once.

I wonder whether the gradual switch would need to be made possible through something similar to a micropayment subscription model, which is non publisher specific.

I don't want to commit to subscriptions for 5+ publications, but I'd happily buy a days access occasionally. This feels much more akin to buying a newspaper in the old world.

I think we'd end up seeing positive changes. Especially the end of content producers being held to ransom by advertisers and commercial pressures.