Pieter Wuille https://twitter.com/jb55/status/1133533068197675010
1. The first owners of possible computers with the ability to 'frack' the privatekey will use these computers only for shalecoins. (Coins with no holder)
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No such thing as "fracking" private keys of old unused coins in the foreseeable future, even accounting for quantum computing.
Note that Pieter Wuille's quote above refers to the public key of an address being exposed while sending a transaction from it. Old addresses that have never seen any outgoing transactions have never exposed their public key and can thus not be "fracked" by quantum computers. Neither Bitcoin nor quantum computers work that way.