Oh, I have. They usually respond three months later (i.e. two months later than they're supposed to) with some noncommittal message.

It's not a problem of a lack of reporting.

That is interesting. Ok, then you should follow up with them and ask for how your case is progressing and do a write-up if you do not receive a satisfactory answer.

I honestly don't have the time and energy to chase a non-functioning entity that I have no effective way of forcing to do their job.

I do donate generously to noyb.eu, which is using those donations to hire full-time people to do exactly that, plus trigger lawsuits where necessary.

I did talk to people working DPAs though, and they seem obsessed with the irrelevant small stuff (particularly keeping people from easily communicating via e-mail is their pet peeve, ignoring the improvements in transport security that happened in the past two decades since they developed their policies), instead of dealing with what affects everyone.