The answer is complex because I don't really like pizza, but I DO occasionally eat it, when I'm in a strange mood. And yes I do like pineapple on pizza. The fruit/sweet cuts through the salt/grease of the pizza, balancing the flavor - to me this is not different from putting cucumber or tomato on a sandwich or another savory food (cucumber and tomato are both fruit!!!)

I think that a lot of people who are downright repulsed by pineapple on pizza just need to give it a shot! Especially if it's just the idea of fruit on a savory/salty food that bothers them, because they probably eat fruit on savory foods more than they realize....

Oh wait I have to be controversial and aggressive with this opinion right? Um.
If you do not like pineapple on pizza you have the palette of a BABY and a COWARD,