It can't be stopped, and I'm not sure it should be.
Many if not most long-haired women eventually get tired of either the upkeep or look. At least some of them can make some money doing haircut videos or selling their hair. And some of the haircut videos actually start out as great long hair videos with brushing, styling, etc. If you want to see some gorgeous long hair, check out the women selling their hair at buyandsellhair.com or hairwork.com.
If these women were unable to get money for their long hair or simply unable to find support in making a change, they and other women might never give very long hair a try at all. Some women grow their hair out repeatedly for the explicit purpose of selling; otherwise they might just keep short hair all of the time.
I would much rather see a lot of women try out very long hair for some number of years and then cut than see very few women ever try very long hair but keep their long hair forever, even after it stops looking good.