At that point... they could just make it official and say "$1 net worth = 1 vote".

It's not like reality is that far from that already, when "1 person = 1 vote" can only cast their vote on a representative financed by someome with large enough net worth, then discard a bunch of "1 person" votes, and end up with "1 representative = 1 vote" who can further be lobbied based on someone's or some company's net worth.