"No, I claim that legacy miners will be spending BTC that was erroneously sent to “anyone can spend” addresses that have no public/private key “rightful possessors” in Satoshi’s legacy, immutable 0.5.3 protocol. Those who are foolish enough to believe the Core scammers and send their Bitcoins to addresses which the legacy protocol can’t recognize, have willfully donated their Bitcoin to the legacy miners."

Honestly, this is not substantively addressing the point. Whether you call it them 'erroneously donating' or me calling it theft, THEY will call it theft and scream bloody murder. It will cause every BTC HODLer to do due diligence before they subject their possessions to transactions, and every potential investor in BTC to do the same. If this happens to more than one HODLer, there will no market for BTC at all, because there will be no confidence that transactions won't result in simply losing the asset.

I don't think you've addressed this actual demonstrable affect that widespread dispute over who owns assets at all, because Mt. Gox, Ethereum, and many, many non crypto disputes have shown that insecurity of an asset alleged by more than one obviously crazy or fraud bent accuser drops the value of said asset and dries up markets like nuclear fires do the morning dew.