If we want crypto currency to be a currency we have to keep spending right? But at the same time it's something worth keeping too since I do the same with my fiat in bank for more than 2years without touching it. Is it possible to say that Bitcoin in every wallets for the past 2years without moving are considered lost due to death or lost recovery keys? It's pretty hard to believe that anyone won't come back for their Bitcoin after 2years with no activities on the wallet.
If Bitcoins are there in the wallet for long term, that doesnt mean those coins are lost. It maybe the owner is Hodling for longer period of time. If you generally have a big amount of Bitcoins, then you wont be that much careless that you will forget the private key of the wallet. As I have seen generally the long term holders dont touch the coins for 4 year cycle, they invest for 4 years altogether. So yes we cannot just claim that those Bitcoins are lost. And comparing Fiat and Cryptos are completely useless. Both have different features and they are completely different.