They even have a flavor in most restaraunts called sweet and salty which is just sugary syrup added to whatever savoury sauce. So it’s not like it’s an under represented flavour either. Like I get some people have a simple palette that can only handle one flavor at a time. Maybe they can learn to accept all of the rest of us who like combining flavors.

I just think pineapple tastes like ass on or off pizza ¯\_(ツ)_/¯

The only reason people get worked up over pineapple on pizza is because there are extremely few places that do it correctly. Most just open a can of frozen chunked pineapples, plop it on and hope for the best. It makes the dish disgusting. Also doesn't help that certain areas of the world prepare the rest of the pie in a completely different manner resulting in very different flavor and texture experiences. A Chicago style with pineapple would be very different from new york style with pineapple.

I've also had properly made pineapple pizza before and subjectively speaking, it was just ok at best. Not anything to rave about or get up in arms about, honestly pineapple has more than just sweet in it's flavor so it still tastes off and doesn't vibe well with the rest of the ingredients like your other examples do. Only a select few people will like it. Probably the same reason most fruits aren't used with pizza like strawberries or cantaloupe.

Combine both those things together though and you get a recipe for a controversial dish.