Yes, language does evolve. For example, American English has evolved in such a way that "beg the question" now means "raise the question" to the vast majority of people in the year 2017.
Forgive me, but I think you're in the minority of people who bristle at the contemporary usage of this phrase, which makes you come off as incredibly pedantic.
I literally could care less about "begs the question". The formal use can be depreciated - we're not likely to staunch that floe. But irregardless of my feelings, people who flaunt the official meaning and right "begs the question" in the increasingly common usage have the wrong affect - they sound like they're putting on heirs - "raises" or "brings up" each sound more naturist.
(Yes, that was fun. I hope you like it, too!)
Kind of like how "I could care less" actually means you don't care at all, despite the literal interpretation of the sentence meaning that you're capable of caring less, which means you DO care.
Language evolves - things that start out as misunderstandings or errors become informal usage, then dominant usage, then the correct way.
Others stay misunderstandings or errors.
It pays to learn the correct way so you sound educated as you speak, and so other educated people don't automatically discount what you say, but there's little benefit in attempting to correct others.
That said, mis-using erudite words or phrases spoils the effect.