Dancing,
““What type of sheitel did my grandmother or great-grandmother wear? Was it as long, flowing, and natural-looking? Surely not; it was short, stiff, and wiggy-looking.”
You remind me of a true story; one ultra frum yid in Jerusalem that was makpid not to have a phone in his house – why? He explained being that “in the Heim in his shtetll we didn’t use one”. When he told that to an Adom Gadol, he answered him: you know why they didn’t have one?
Because there was none!
If Natural looking hair would have been available – they would have had one.
The שלטי הגיבורים case is simple – one is permitted to take her OWN hair and cover herself and walk like that in Reshus haRabim. That means, a Kallah getting married can cut her own long braids and use that as a covering. Period!
(Note, the Levush does argue on using ones own hair)
“The same מגן אברהם that you quoted that brings the שיטה of the שלטי גבורים HE himself harshly prohibited even unmarried girls (whose hair is not yet consider ערוה) to go out with long loose hair because it’s פריצות!”
Why are you confusing two different issues?
One is about natural looking hair in a MODEST form (whatever you define “modest”), which is Muttar as per final poskim – even if it looks exactly like hair! And then we have the issue of immodest looking Shaitels – which is an issue on its own, even if it would to be synthetic.
Wearing a bright red scarf can also be an issue of Tzinuos – will you asser all scarfs then?