Yes it’s societal values, you’re framing the narrative much too negative though. Old age for women isn’t all bad, older women stereotypically radiate trust and comfort for example. Look at Betty White and Dolly Parton, their age is a strength to them.

My previous comment was just about beauty. Superficial, societal, subjective beauty. Women are much more beautiful than men in general, but that usually fades with time. The beauty of men never tops that of women, but it can still grow with age.