Mcgonagall doesn't abuse her children in class, but she abuses them outside of it. She lets the weasleys boo and heckle first years. She let the marauders reign terror on the entire school on general, edcalating to sexual assault and attempted murder in particular. She punished a neuroatypical child for having memory problems by locking him out at night with a mass murderer on the loose. Am i the only one she scares, the only one who has flashbacks from such a biased teacher??
McGonagall is strict, but I would not say that she’s biased or abusive toward her students. And I say this as someone who is not neurotypical.
When we meet McGonagall, she breaks down into tears over Harry’s parents’ deaths and is extremely concerned for his well-being at the Dursleys.
And yet, she maintains an outward expression of complete neutrality.
There’s evidence to suggest that she has a soft spot for Harry, but she’s also not afraid to bawl him out when she believes he deserves it. She punishes him harshly for being out of bed after hours in PS, is “white-lipped and furious” over the troll incident, threatens to take additional points if they go anywhere near the Philosopher’s stone, rebukes them for the flying car incident, calls him out in Transfiguration class, and gives him detention for getting himself into trouble with Umbridge. This isn’t to say that she doesn’t stand up for Harry at times, but I believe she toes the line very well.
Was McGonagall’s punishment of Neville harsh? Perhaps. But from her perspective, Neville had foolishly written down the passwords and then lost the paper, making it almost laughably easy for a murderer to attack her students in their beds. Neither she nor Neville knew that Crookshanks had stolen the password list.
It’s worth mentioning that McGonagall is never described as targeting Neville. She’s quick to intervene when when Malfoy takes his Remembrall, is angry at Harry for getting Neville into trouble over the dragon (“I suppose you think it’s funny that Longbottom here heard the story and believed it, too?“), and doesn’t draw attention to his mistakes in the classroom. Which certainly can’t be said for several of Neville’s other professors, most notably Snape.
To cast McGonagall’s relationship with Neville in such a negative light seems to almost willfully ignore the HBP scene in which McGonagall defends Neville in no uncertain terms:
“Why do you want to continue with Transfiguration, anyway? I’ve never had the impression that you particularly enjoyed it."
Neville looked miserable and muttered something about "my grandmother wants."
"Hmph,” snorted Professor McGonagall. “It’s high time your grandmother learned to be proud of the grandson she’s got, rather than the one she thinks she ought to have - particularly after what happened at the Ministry."
Neville turned very pink and blinked confusedly; Professor McGonagall had never paid him a compliment before.
"I’m sorry, Longbottom, but I cannot let you into my N.E.W.T. class. I see that you have an ‘Exceeds Expectations’ in Charm however - why not try for a N.E.W.T. in Charms?"
"My grandmother thinks Charms is a soft option,” mumbled Neville.
“Take Charms,” said Professor McGonagall, “and I shall drop Augusta a line reminding her that just because she failed her Charms O.W.L., the subject is not necessarily worthless.”
As for McGonagall letting the Weasleys harass first years or the marauders “reign terror,” I would take issue with both the characterizations of the marauders/Weasleys general behavior as well as McGonagall’s ability to control it. For whatever else she is, McGonagall is human, and cannot be everywhere at once.