Personally I don't have as much of an issue with when they're poking fun at him per se, but when they denegrate or damage things he has clearly worked hard on and put a lot of passion into, that's crossing a line for me. It becomes incredibly mean-spirited.

There are two examples in this compilation video. One at the linked time, and another at 6:33. Especially with how happy he is to see Leslie in the second clip until she destroys his art. It's honestly heart-breaking. The pie to the face that came a little bit before that was also hard to watch and really felt mean. Dunno if that's because of how cold and calculated it was (vs the more usual off-the-cuff comments), or because it was a physical act rather than verbal, or something else. But I didn't like it.

It feels cringe (to me) cause these type of people are often bullied in real life work places, again with no real reason.

It's the opposite of the Lil' Sebastian thing, where there's that horse that everyone idolizes for no discernible reason. Although with that, there's the one character who doesn't understand why they do that, so maybe that's what the Jerry thing needed? Or perhaps that would have made it even sadder lol.