You do present a valid flaw of a hypothetical one-time remotely possible transaction that may or may not exist. Do you have a solution that does not involve a hard fork? Because I am sure a hard fork also has many more hypothetical flaws.
no, because any solution involves people upgrading to have that solution.. and so the only real solution is to stop playing the "everything is ok" card, blindly turning old full nodes into less then full nodes.
but to instead say.. look everyone its time to upgrade, THIS MONTH
doing all the crap like saying its safe not to upgrade. or 12 month grace periods so no one hash to rush or bother right away does absolutely nothing to kick people up the ass to upgrade. meaning things can go wrong.
the only solution is to not have such lax policies.
but it this way. what would have happened if in 2010 peopler were told, dont worry about the millions of bitcoins created in 1 transaction.. we will give you 12 months to upgrade everything is fine
what would have happened in 2013 when the DB bug became apparent. and the devs told everyone.. dont worry you dont need to go above 500k limit we will give you 12 months to upgrade in your own time..