I don't hate the episode, but even despite my contrarianism I have to admit I've been brought around to agree that it was a very bad episode for the universe even if it was an OK episode internally. It's easy to forget if you are young and you've never lived in a world where Simpson's seasons 1-7 or so are all there was in the world, but the Simpson's used to actually have a universe, rules, characters that were more than walking stereotypes, and even a bit of capacity for lasting consequences, and thus, a capacity for drama that the modern "cartoony" (in the bad sense) version has a very hard time sustaining.

If you were raised in the modern era, you can get the reverse effect that some of us oldster's describe by going back and watching Season 1 in order. It is not the best season, but it was already showing a lot of the promise that would manifest a couple of seasons later, and in so many ways you'll find it is just a different show, even more clearly than if you go a couple of seasons later. (And it does have my favorite Halloween episode. I have to admit I haven't seen them all, and there were certainly some other good ones, but when it comes down to it, it is hard to beat a dramatic reading of The Raven. There's a reason this became a tradition and not just a one-off.)

I enjoyed it retroactively because it set up this continuity gag a few seasons later: https://www.youtube.com/watch?v=6rxdhKRODLw#t=59s

It might be a good episode, but it's bad in the context of the whole story arch

It’s not that the episode itself is all that bad in and of itself. Fans think of it as a turning point in tone (changing the long time Skinner character). Think of it as the beginning of the very long and steep decline.

Same.