Sure, but only for young women. Look at women as soon as they became mothers or hit 35+ in the 70s, and pretty much all had short hair. (All throughout the century very young women often had long hair, but normally switched to cropped or short permed or curled hair as soon as they stopped being young and/or available.) My mum had gorgeous long hair in the 70s as a young woman and young wife — until she got pregnant, and then swiftly got a short Purdey cut like all her mum friends!
(Remember that then, in the 80s and well into the early 90s, women were largely advised to get a “low maintenance” short hairstyle when they had small children! I have all my mum’s baby books which I reread for fun when I had DD — and they all actually advise this!)
And most boomer age women had kids in their early to mid 20s — so it wasn’t that long that they had the lovely long 70s hair for!
Re trousers, oddly though for the boomer generation they didn’t take to trousers until the 90s, the older generations, like my grandmother’s and her age friends, were often wearing “slacks” the whole time. Women wearing trousers in fact looked old-fashioned and grandma generation during the 70s-90s, and not particularly radical, precisely because it had been so popular during the fifties and sixties for that generation of older women (perm & set, slacks and jumper!)
This is only to illustrate that the idiocy and shortsightedness of young TRAs claiming that “gender non-conforming” dress is equal to short hair and trousers, when most older women routinely wear that and women during the 20thc. always have done. The very gendered clothing of the last two decades (bodycon, long swishy hair, tons of makeup, Kardashian style look) is very recent. Young people (I work with university students), tend to assume that this is how women have always dressed up until now, when it’s a style that dates from post-2000 anyway. They are routinely amazed when I point out that we didn’t dress like that in the 90s.