Privacy-Preserving Age Verification via Bank

Probably a bit out of hand on this one, this is more merely suggested as one of potentially many more privacy respecting options as that's what's realistically being discussed here as both many people and Fluxer has/have mentioned:

Some regions have enacted laws that require online platforms to verify users' ages using methods we are either unable or unwilling to implement, such as government-issued ID uploads, biometric scans, or mandatory third-party age verification services. Rather than implement these methods, we restrict access to Fluxer from affected regions.

Realistically, I'd presume, at least for a while that age verification would probably not be done as it's mentioned above - at least this is my understanding. Though, not saying this solution I briefly mentioned is the be all and end-all, I'm not 100% sure on how the other proposed solution would work, as having the bank email Fluxer would likely cause a larger amount of admin on Fluxer's end - if said Bank(s) are willing to do this? I've not personally heard of this but presume it may exist in some places.

It's not uncommon for kids to have access to their parent's credit card number, and I don't imagine countries with age verification laws would accept this as valid.

This is a true and valid criticism of the way age verification currently works however, Ofcom (UK Regulations) says the following:

... sets out a non-exhaustive list of methods that we consider are capable of being highly effective. They include: open banking, photo ID matching, facial age estimation, mobile network operator age checks, credit card checks, digital identity services and email-based age estimation;

If the regulations allow for a more privacy respecting option, then surely it's best case and we can't really guess what's coming for any one particular country.

Same in Ireland, people rarely have credit cards, everything is done with debit. I wouldn't want to be ordering credit cards just to confirm I'm an adult on a messaging app.

Agree, with the statements mentioned, however again this is more about what Privacy Respecting options there are, and this currently seems to be one of the better, and allowed options at this current moment in time. Plus as mentioned in comparison, larger multi-national corporations like Valve are doing this, so there is proof that this at least works in the UK.