Pineapple is objectively the best pizza topping because it's one of the only toppings which makes pizza into a fully rounded scientific flavor experience. The five flavors which we can detect are sweet, salty, bitter, sour, and umami (savory). A basic cheese pizza covers two, maybe three of these flavors — salty, umami, and maybe sweet, depending on the sauce used. Pineapple covers three flavors — sweet, sour, and bitter (if it's fresh). This means that pineapple pizza fully features all of the five flavors.
What other topping can you say that about? Not pepperoni, nor olives, certainly not mushrooms or sausage. No other pizza topping as perfectly rounds out the flavor profile of pizza as pineapple, especially fresh pineapple, and that is why it's the superior topping.