The issue isn't whether this HT is a nice guy or good at his job or whether genuine complaints get ignored.
The issue is that some parents complain all the time, unnecessarily, and make the lives of school staff more stressful than they are already. Some of them are desperate, for whatever reason, to get a perfectly average, reasonably behaved (in school, at least) child diagnosed with something. One mother of my acquaintance complained and complained and complained that the school was recognising her child's issues, and the child was on the autistic spectrum and goodness knows what. She took the diagnosis all the way up the line and the final word was that the child was suffering from mild anxiety - and no bloody wonder, given how the mother had carried on. She took up loads of SLT and SENCO time and caused a lot of stress.
Another parent of my acquaintance complained persistently about a TA. Her child had no diagnosis, but was still being given 1:1 TA time every day (taking the tA away from the rest of the class). The TA had the temerity to try and make the child do some work, so the mother complained to the teacher that the TA was picking on her little darling. This caused a couple of terms of stress for the TA, who is the kindest of people.
I have said before on school threads that I have nothing but absolute respect for parents of children with genuine issues who support them, fight tooth and nail to get EHCPs for them, and advocate for them to the school (and the school where I was employed worked very closely with such parents, and achieved some incredible outcomes).
But there are some parents who have completely unreasonable expectations and want everything their own way. When that doesn't happen, they complain to the SENCo, and SLT in general, and then directly to the HT, and then to the chair of governors, and then to County. Some of them behave in a totally inappropriate manner, including all over social media. A shot across their bows like this court case is, IMHO, a bloody good thing.