So the “mares eyin” of years ago (which was in reality not mares eyin), is absolutely not relevent to the wigs of today.
Obviously today’s wigs are more realistic looking, but R’ Moshe addresses a wig which looks real so that people can’t tell.
Still, he holds it’s muttar; the fact that today’s look even more real in comparison doesn’t change the halacha.
Even though people in those days may have been fooled by those wigs, since we are used to more realistic looking wigs, they wouldn’t fool us because we are used to seeing more realistic looking wigs and our eyes are longer tricked.
The same thing will happen with these shaitels too; we will get used to them and they will no longer fool people I to thinking they’re real (many can already tell the difference) until the next innovation comes along and the poskim will undoubtedly have the same debate again, with the osrim saying that even if you held the lace are okay, theses new ones are definitely assur.