if it becomes painfully obvious that shor's algorithm will be able to steal from a type of vulnerable address in real life, I'd be okay with hourglassing that type of address. only 1 spend from vulnerable types of addresses per N blocks, enforced at the protocol level. but not before it is obvious. you would have years to migrate. bitcoin is simply not mature enough to be a set-it-and-forget-it store of value and anyone who thinks otherwise is delusional. but outright confiscation is beyond the pale for me.