> Probably the same is true for those cards you linked, they're special "youth" cards that platforms could in theory block?

Nope, there’s nothing “youth” about them, they’re more like safety features. The cards I’m talking about act as real credit cards. Plus, I forgot to mention but there are also services (even provided by the banking networks in the countries themselves) which allow you to connect an account (or deposit some money in) and get temporary credit card numbers for online payments. I’ve used them and know multiple people (also adults) who still do.

> Basically, filter by the card type, assume credit = 18+, any other might be under 18.

My point is that maybe that’s enough in the UK (is it?) but you probably wouldn’t be able to rely on it for every jurisdiction.

To be clear, I like your idea in general and would not want to discourage you from it—quite the contrary—I’m just alerting to the fact it might need further though so you don’t end up sinking time on something which wouldn’t work.

> Yeah, referrals ala Lobste.rs.

I wasn’t aware that’s how they worked. I’ll have a read. For anyone else curious:

https://lobste.rs/about#invitations

Thanks a bunch for describing it in more detail, actually very helpful!

And no worries, nothing discouraging, discussing the idea with others no matter their reaction tends to do the opposite for me, so thanks again for taking the time :)