1. It is practically impossible to enforce. Maybe exactly the right amount of money changed hands in one transaction, but how do you know there were no other related transactions perhaps via anonymous crypto transfers or entirely off-net (the good 'ol brown envelope full of cash) or by non-monetary exchange (service rendered).
2. It punishes the final buyer, so the scalper in the middle doesn't care. It may put buyers off so reduce the competition and the prices scalpers can command, but it won't stop them completely. For every scalper that decides it isn't worth bothering because profits are down 50% (figure plucked from thin air) there will be a queue of smaller fish more than happy to take the remaining margin.
Look into attempts that have been made to control big-name concert tickets and how they have all failed - the problem is essentially the same here.
ie I naively buy a domain for a too high price, and then the registrar revokes the domain? The seller ends up with the money, and I end up with nothing? A smart seller could possibly even snatch back the domain from the registrar?
domain transfer: $49.00
totally unrelated consulting services: $49,951.00Also, most desirable names would not be put to productive use since there'd be no relationship between what you can do with a name and how likely you are to get it, though this is a handwavier point.
Twitter (and Instagram) ToS prohibit selling handles and yet I've been on both sides of those transactions before. You just offer the person a "consulting" contract, part of which is delivering the handle
State socialism specifically.
Could you expand on that? People tend to use widely different definitions of "communism" so I'm not sure what you mean by that.