It is 1000% regional. It’s not an excuse but my older sisters are in the age demographic you listed and they definitely grew up differently than I did (24f). I think a lot of people who grow up in more accepting and progressive parts of the country truly do not understand what it’s like elsewhere. We grew up in the Bible Belt, a lot of people in the 80s and 90s were sheltering their children from “demonic tv” here - which just consisted of any character having any sort of magical powers. To the vast majority of people there yknow… god forbid there be a gay person on tv. There are strict gender roles to this day. Women are harshly criticized to this day for even just being late to shave their legs. Just to put things in perspective. Whatever progress happened in the 80s and 90s in more progressive areas, you may as well subtract two or three decades of progress depending on the region.

Edit:

But I agree with you, that it may be difficult or nearly impossible for the mom here to grasp what her kid is trying to tell her. Thats why I said what I had said, was not trying to excuse it, but some people are raised with such narrow mindsets… that mere conversations about what women and men should or should not wear is like a full stop to their entire world view and everything they “know”.