Free products sooner or later end up becoming walled gardens unless it is open source and self hosted.

How about paid businesses models? Aren’t we ripe to start these now?

By definition, paid products are walled gardens from the beginning.

I'm not a huge fan of medium either, but I was able to scroll through the whole article without logging in. There's a prompt at the top, but nothing too obtrusive. I even tried with ublock origin off. What am I missing?

Medium is extremely inconsistent with their account-/pay-walling. I think it’s intentionally chaotic and confusing to drive signup/subscription rates that wouldn’t happen if they communicated clearly what limits you’ve actually encountered.

It didn't ask me for a login (?)

depends on whether you've finished your free articles for the month

And whether you have an ad/tracker blocker.

Ah, I sit corrected. I have the blockers and don't think I've ever used Medium before.