To play the devils advocate. I see the same people on this thread who are bashing red sea on all red sea threads recently. None of them seem to have any actual experience with red sea however..
Of the 3 examples posted, only the 2 from reef2reef were actually G2s (the other post being from 2019 is obv not a G2). Of the two remaining examples - one the user has yet to follow up with additional information or video evidence, and the majority of commenters on that thread agreed the initial video proof was far from adequate.
I owned one of the Fluval Flex's and that community was the same way, the tanks which had issues were made loud and clear online, and the large majority of tanks with no issues were never heard from again, as is most consumer feedback.
If you go to Waterbox forums for example you can see how poor their customer service is directly from that userbase.
All tanks have failures, I don't think there is something catastrophic happening with the new G2s as some are pushing so desperately.