Anchovy is reliant on the pizza variant. On the Americana regular (puffy bottom/dough width noticible) or variants where the sauce/cheese middle exceeds 1 1/2 inch+ contact from topping to crust (Chicago/Deep Dish) Anchovies are not properly utilized in these dishes, and serve as just salty bits.
To utilize Anchovies properly, you need a thin crust, or a thin sauce. Silician, Flatbread, New York style, and Pan style utilizes Anchovies well.
The purpose of anchovies on pizza is to both give a bit of salt, however on a thin slices, the achovies release their oily grease and become delicious bacon like slices.
Your pizza anchovies should be like a long bacon bit essentially.
Pineapple however depends on the time of day, meat variation, cheese utlization and again, consistency of the dough/sauce.
Pineapple cooked on a thin slice loses its sweetness and is genuinely unpleasent to eat, unless eaten with ham/bacon with it.
Mixed with a robust Marinara in a typical Americana dough consistency, makes for a good brunch/early afternoon pizza, however you need to add the topping on the near end of the bake, rather than a full topping bake.
The problem is that people tend to fully bake the pineapple, and thus the grody factor comes in.
You only fully bake pineapple if you have something to compliment it, like ham.