Go fuck yourselves.

Sincerely, Everyone in the industry

If it's working right now, an update can only cause it to break. The best case scenario is that it still works. Why would your roll the dice?

Every single place that I ever worked at in a past 20 years tests payments using real cards and real API endpoints. Yes, refunds cost a few pennies and sometimes can't be automated, but most payment providers simply do not offer testing APIs of a sufficient quality.

Situations when a testing endpoint has one set of bugs not found on production and vice versa used to be so ubiquitous in mid-2000 to mid-2010s, that many teams make a choice agains using testing endpoints altogether - it's too much work to work around bugs unique to the environment that no real customers actually hit. And now the whole generation of developers grew in a world of bad testing APIs of PayPal, Authorize.net, BrainTree, BalancedPayments (remember them?), early Stripe, etc. So, now it became an institutional knowledge: "do not use testing endpoints for payments".

To be exact, people often start using testing endpoints for early stages of development when you don't have any payment code at all, but before the product launch things get switched to production endpoints and from that point on testing endpoints aren't used at all. Even for local development people usually use corporate cards if necessary.

I have a suspicion that things may be different in the US, with many payment providers' testing environments simulate a typical domestic US scenario: credit cards and not debit, no 3d-secure, no strict payment jurisdiction restrictions, etc.

Does some central authority have access to and the compute power to correlate all of the data available in those video feeds? No

My own mother died of Ovarian Cancer at age 40 and used talc. I'm not confidence for a second there is sufficient evidence to even hint at causality.

[1] https://www.thestudiesshowpod.com/p/episode-3-aspartame