I have been on both sides of this. As a coach and youth leader I experienced over wrought parents who knew how to do things better from the stands. I told them to knock it off or get out with me and help. They knocked it off or left. Pity their kids.
On the other side I have a child with ADHD. The school system handled him poorly. We tried to work with them, but having the parents involved with bs. We were not consulted, but told. We were lied to about his placement and education. He was railroaded into a non-education program until we got legal help to sue for compensatory education.
We won, but it took 4 years. and the teachers who could have spoken up about what was wrong all lied. And none were held accountable. The school district paid, but not those who betrayed our child. It sucked.
I agree that we should give some a chance, but when they betray us we should not stand back and take it. If you do not advocate for your child, there are few others who will. Give them a chance, but if they screw up then let them have it.