• You can only interact with nether pizza with an empty main or offhand, and the pizza slice item doesn't try to combine with other pizza slice items in your inventory, which is super annoying (see video)
• Also, if you have an empty off hand, the pizza will place itself in the offhand, which is not really like any other interactable block in the game

• Unlike cakes, pizza do not output a comparator signal based on how many slices it has left (screenshot from the minecraft wiki)

also, the pizza texture z-fights when you put a comparator next to it :3