As far as I understand, the problem with sheitels which look like real hair is one of maris ayin, as it looks like the person isn’t covering their hair.
This may well have been true several years ago – apparently one would see a woman with such a sheitel and wonder “did they get divorced/ go off”. However nowadays even the most insulated meioh sheorim Rebetzin knows perfectly well that they are sheitels designed to look like real hair. Even if they honestly had no way of telling at all, they would still assume that it was certainly a sheitel. They wouldn’t suspect the person of going off, just of not following her own standards of sheitels, which are highly praiseworthy like all Prishus, but halocho is not mechayev them. Or they would quote psokim from 30 years ago when realistic sheitels did have a maris ayin problem.
Have any poskim said RECENTLY that realistic-looking shaitels are OSSUR (not just “in my opinion this is a loathsome”), and if so what is their rationale?