wallet != address != person

A wallet is a collection of addresses. So let's not confuse things here, you cannot truly know how many wallets are out there because you can't link addresses belonging to the same wallet unless the owner spends some funds.

Furthermore "addresses" do not map one-to-one to people. Many addresses can be owned by the same individual. Or a single address, containing many thousands of bitcoin could be just the cold storage of an exchange, and thus actually being mapped to several thousand users.

So these analyses are a bit tricky.