The strong collision avoidance guarantee is mostly a result of the large space of hashes those functions generate. So, yes, if you have a hashmap with 2^128 sl

The strong collision avoidance guarantee is mostly a result of the large space of hashes those functions generate. So, yes, if you have a hashmap with 2^128 slots, you're technically right. But you don't have a hashmap with 2^128 slots. So you have to smash that output space into a smaller space somehow. And then you're back to considering what to do when you have collisions.