It's sometimes good to use a smaller size. Many string/dynamic array libraries e.g. will use 32-bit types for size and capacity even on 64-bit platforms to cons

It's sometimes good to use a smaller size. Many string/dynamic array libraries e.g. will use 32-bit types for size and capacity even on 64-bit platforms to conserve space, and by that virtue also be more cache-efficient. I think the Zig compiler also explicitly uses 32-bit types in a lot of places, even though it's targeted mostly for 64-bit platforms.