I think the lack of warning makes a stronger case than concentrating on a report. HQ has said that they follow a procedure, and for whatever reason that hasn’t happened in this case.
Reports lead to deletions - we know that. But they shouldn’t lead to an automatic ban, as they are, at face value, just one person’s dislike of a post. As I’ve said before, when people say ‘I could report you for that, but I won’t’ I imagine them in the playground sticking out their tongue. The assumption is clearly that their irritation at a post will be shared by all, and it won’t be. Flagrant rule breaks or illegalities should be reported but clashes of personality are just that.
There have been times when it was obvious why posters were banned - even when their friends are angry about it, but in this case (and IMO in the case of growstuff) there was no obvious reason.
If HQ feels that perhaps they acted in haste, or that the process they advertise wasn’t followed, that makes a clearer case, IMO, than the muddy waters of reported posts.