what about HD wallets that generate unique addresses each time a spend is made and you have funds scattered around many addresses?
You can either move your complete balance to one linked address or you can sign a message for all addresses, one after the other. Sounds like a lot of work with signing but actually it could be faster because you don't have to wait for slow bitcoin confirmations!
message signing is still hard or not yet possible natively with hardware wallets. so there's only the option of moving all funds to the one address.