I don't see this as related - your account triggered some abuse detection - did you ever go to them and validate what you're doing is covered by the terms you're paying for ?

I mean it sounds like a dick move by Backblaze, but comparing it to what OP is describing is downplaying how bad this looks for GCP IMO.

Going through with official contact at GCP, being assured he did everything right and that it was taken care of - and still getting shut down. In my book that's just inexcusable - if you can't count on that kind of support to work then how can you rely on that platform for anything ?