What is page table entry size?

Question

I found this example.

Consider a system with a 32-bit logical address space. If the page size in such a system is 4 KB (2^12), then a page table may

Answer 1

As for why a PTE(page table entry) is 4 bytes:

Several answers say it's because the address space is 32 bits and the PTE needs 32 bits to hold the address.

But a PTE doesn't contain the complete address of a byte, only the physical page number. The rest of the bits contain flags or are left unused. It need not be 4 bytes exactly.