Well, "liberal" means that you want individual liberty, free markets, and limited government intervention. That's just the way words work. Isn't that special?

Like, if a word starts being used, and people are all like, "not what the dictionary says but I get it", then the meaning changes or splits, like this.

So, no, prescriptive language only works if fiercely guarded or if it also matches descriptive language. Neither is particularly true for "feminism" as "equal rights for women" and no more connotation beyond that, so the meaning is shifting.

I think it's a shame, but I am not going to pretend it's not happening.