Ron Paul and maybe Massie are about the only politicians of my lifetime that held any real power that I can think of that would even entertain deregulating machine guns.
Which is also why the Forced Reset Trigger was not banned - they didn't think they could.
The ruling on those had nothing to do with overruling any part of the NFA. Only correctly identifying that FRT and bump stocks do not shoot automatically more than one shot by a single function of the trigger, which is what congress said would be the things allowed to be called machine guns.
Of course, some machine guns would always remain valuable for their desirability as antiques, as long as people remain interested in them. That presumption of future demand for your collection might be a relatively safe bet for cool old guns in America, but it's still a bet.
2 things make me question this. Never is a long time. People who claim to know the indefinite future, generally don't. These things being understood, forgive me if I don't take your word for it. Nobody should.