What wil happen to old Bitcoin wallets whose private keys re considered forgoten

[Catenaccio]

Well that's a big "if" since this goes against Bitcoin Principles. Nobody should be able to take other people's coins even if they are lost. So I don't think such a proposal would ever gain majority's support. But "IF" it did, then yes anything is possible to change. Bitcoin is just code after all and you can change anything in it. For example you can make it so that you can spend any coin that is 50 years old (2059 for first blocks' reward) at block height 2628000 and receive it as its reward as the miner. But would you be able to get the majority of the network to agree to that? I don't think so.

They will try to make forks as same as how they did in 2017 with Segwit. They will still have bitcoins on initial Bitcoin blockchain, but they will have shitcoins on a forked chain. They as people stands behind the fork will not lose anything, they get more coins, even shitcoins but will help them having some extra money.

For proposal to take over bitcoins of the others by any reasons including quantum computer threats is very non sense and against Bitcoin principle.
How Many Bitcoin Forks Are There? You will be surprised!!!

[tiCeR]

...

Well that's a big "if" since this goes against Bitcoin Principles. Nobody should be able to take other people's coins even if they are lost. So I don't think such a proposal would ever gain majority's support. But "IF" it did, then yes anything is possible to change. Bitcoin is just code after all and you can change anything in it. For example you can make it so that you can spend any coin that is 50 years old (2059 for first blocks' reward) at block height 2628000 and receive it as its reward as the miner. But would you be able to get the majority of the network to agree to that? I don't think so.

Yes that is what I thought and that is why at the end of the day I think calling bitcoin a social consensus system is actually the best way to take into account that in theory anything is possible. But I agree with you that there should be no minority for a change like that, but it is all about "IFs" as you pointed out.

[PVequalNRT]

What I know, BIP-360 will solve the exposed public key problem but it won't automatically solve old wallets problem, BIP-361 comes after that and there is proposal to freeze unmigrated funds but many are against it.
So it's still unclear what would happen but the BIP-360 upgrade won't automatically move the funds like you expected and whole community still exploring for a better solution. Let the expert find the definitive solution I guess, until then just wait and see.

Prior to other coin migrations I have seen, even though there was nothing like quantum existence, all migrations were done by people that have access to there private keys. In this case, no matter the approach of the team, there will be announcement for everyone to move their coins and there is going to be grace to when it will stop. If quantum is yet to be active or public that time, the coins that are not yet to be move will be there until quantum becomes real and problem to all of us.

[Nothingtodo]

If Bitcoin is at risk in quantum computers, then I would say that Satoshi will definitely think about how to secure Bitcoin by becoming active again. However, if quantum computers can change the cryptographic algorithm of Bitcoin, then I would definitely say that Bitcoin developers will definitely come up with more updated algorithms to secure Bitcoin against quantum computers. Those to whom Satoshi Nakamoto has entrusted Bitcoin will definitely be serious about Bitcoin. Moreover, if quantum computers can come and reunite all the lost Bitcoins that have been lost forever, then I would definitely say that all the owned Bitcoins and quantum computers will be able to reunite them. Then of course, Bitcoin will be at risk in that case. In this situation, if Satoshi is ever alive, he will not be able to remain hidden, he will definitely come out in public.

[oll]

While replying to this thread The question on the title stroke my head.

Since one day Quantum computer development will be complete and the threat to bitcoin is already publicly being discussed, with bitcoin developers having plans ahead for an upgrade that will protect the network.

My question here is. if it comes to time when post quantum (PQC) is completed, will all bitcoins automatically be moved, or will it require being manually done individually using your wallet? If so, where do those coins sitting in wallets where private keys are considered to be lost stand? Will they be exposed to Quantum risk ? Especially if the wallet links to Satoshi.

Experts say that nothing will be threatened by quantum computers for the next few decades, even wallets such as Satoshi's wallet.
Yes, more and more coins will be lost over time. In general, we have touched on an interesting topic, but let's go deeper into interesting facts. More than 3 or even 4 million of all coins have already been lost forever. Even without converting it into dollars, it sounds shocking. These are crazy numbers.
And how many coins are lost every year?
Of course, no one knows for sure if it's half a percent or a whole percent per year. Which, in my opinion, is also extremely high, but the pace of these numbers is falling. Because there are inheritance services and hardware wallets...