[tshaddox]

I think in practice any English speaker even at like an A2 level wouldn’t get confused, because the context has to be extremely clear in order for “pie” to be used in reference to a pizza. In any conceivable case I can think of, pizza is either going to be explicitly named immediately before saying “pie,” or the context will be undeniable (like when you’re ordering from a pizza restaurant). There would never be a case where someone would ask “what do you want to eat?” and someone would respond with “pie” when they mean pizza.

[anonymouskimmer]

> "There would never be a case where someone would ask “what do you want to eat?” and someone would respond with “pie” when they mean pizza."

Friends or colleagues who are used to eating a pizza together excepted. Maybe rarely someone could say "pepperoni pie" or "cheese pie" without being confused, but as you said the context makes the case in these examples.