In the Banking world, when some money holds in an accounts some specific time without any transaction, We say it is a Dormant Account & It will be moved to banks profit or central authority. Sometimes, Bank just charge a fee every year or month as Administration fee untill the balance reaches zero. So your money is controlled by the banking system.

But Satoshi Nakamotos vision is to decentralized the financial system. Not to implement banking systems rules to the crypto world. So I don't think emptying the stale wallets will ever happen.  Is for some reason, large amount of coin holders decide it is the solution, then we will see a fork to settle the issue.

Just my opinion