Maybe the way to frame it is that MNHQ is regularly invaded by trolls, and it will always be this way because its philosophy is to make it quick and simple to open account, so that people who need support can get it without having to jump through lots of hoops. It is also often beneficial to MNHQ that MN threads appear high up in internet search results (because this drives traffic to the site, and thus advertising revenue).
Unfortunately, this open approach makes the site vulnerable to non-genuine posters, who cause wider harm than the genuine upset caused to the MNers who read the posts before they are taken down. Moderation has to be swift to be effective - so swift that trolls go elsewhere and the problem on MN is reduced / contained.
One way to do this is to have lots and lots of moderators, who can react promptly to problems. I don't know how the numbers at MN stack up, though, but on one board I frequent on Reddit they have just recruited an additional 15 volunteer moderators. I'm going to guess that MNHQ does not have that many mods dedicated to eg the SN boards.
Another way is to use a technical solution, such as auto-hiding any post that gets more than X reports (MNHQ don't need to tell us what that magical threshold is, but I'm sure they could work out what it should be based on the data they have on reports). All this means is that it isn't visible to MNers until a mod has been able to review it. If they feel that it breaches talk guidelines it can be zapped; if they are happy that it doesn't then it will be re-instated. So concerns about "ganging up" on an unpopular poster should be allayed, because their post might be hidden for a while but will ultimately be made available again if that is the right thing to do.And this approach benefits all of MN, not just the boards that traditionally suffer the most from the hairy handed invaders
Then there is the underpinning policy of wanting to educate about disabilism, which informs the talk guidelines. I don't think that this is always applied properly. I think it's a laudable aim, but I've reported posts that I think are just goady but been told that it's standing so that the poster can get an education about disabilism. 
Frankly, that poster often never returns to the thread, and doesn't give a shit about disabilism, because anyone with half a brain would know before posting that what they were saying was out of order - or they know, but don't care. I'd prefer those posts to be deleted and replaced with a standard message about not tolerating disabilism, what that actually means and a link to more information (the My Child Too campaign?)