Is Bitcoin sustainable (not in environmental way)

Various sources estimate that 10% - 20% of all Bitcoin has been lost - mostly due to people who lost their keys or forgot that they had it at some point. We know that there is only ever going to be 21M BTC. How can BTC possibly be a long term thing if you can't replace lost coins - if we are expecting adoption to increase, there will be people who will lose their keys, die without leaving instructions how to retrieve coins, hell, with mass adoption, even dust left in wallets will start to build up. How are we expecting BTC to last if we are almost certainly doomed to run out of coins in circulation at some point?