Will update this post once an official message/post is published, but looking at https://twitter.com/search?q=google%20cloud%20billing&src=typed_query&f=live seems pretty widespread.
"Issues with 'Payment failed notification' is fully resolved On September 22, 2021, you may have received a ‘payment failed notification’ indicating that your payment information was invalid and required updating.
"This issue has now been mitigated and there is no action required from you."
And a link to this page:
Bit like saying if a bank laundered money for the cartel and spookies they wouldn't be allowed to be a bank anymore.
That's how it's meant to work. Google, HSBC, et al are not like me and you. They've paid vast sums to ensure it.