Of the many, many crypto address out there, how many are really being used? I am not asking how many Bitcoin addresses there are. I am asking how many ARE being USED.

I mean, Im sure there is alot of empty Bitcoin adresses out there, but, how many of are people just creating a account and just saying: "Hm, I think I will buy it in a month or so." and then go onto never buy it, or perhaps some who create it but have no intent of using it?

Im asking if there is a way to know a rough estimate of how many people are holding Bitcoin?
One way to know, would be to check 'active' wallets, the ones that have a recent transaction - you define the meaning of recent (1year? 2years? more?).

The problem is that old wallets may still be owned (people just hodling) and accessible, and bunch of wallets are also owned by the same people.

You can use this site : https://bitinfocharts.com/bitcoin/explorer/ to check some interesting data about existing wallets.