This is not a new revelation, I guess it just eluded a lot of people watching the movies.
Palpatine could do it on a galaxy wide scale, Yoda mentions "The Dark Side clouds everything" in the prequels.
I don't remember which, but in various games the Dark Side users had similar powers.
Also, Obi Wan influences the mind of stormtroopers etc. it is a logical conclusion that Dark Side users have abilities like it.
That it is now done in the middle of a lightsaber fight just means the one doing it is trained in this style of combat.
Ofcourse imo it still is bad writing if it works on just about every jedi, in their prime, attacking him in that group.