Is fear broken??

[Necrobile]

I'm new to the server and I played a lot of WoW all the way up until WotLK, and one of my favorite classes to play back then was a shadow priest.  I'm still adjusting to all of the new changes that have happened over the years, some understandable, others lame, but whatever, it is what it is.

I'm only writing because I'm noticing that every time I cast Psychic Scream on an enemy, all they do is sit there, they never run away.  Is this spell broken??  Do they not run away anymore??  I'm playing a worgen on Sylvanas, not sure if that matters or not.

[Necrobile]

I made a warlock and tried their fear ability, and that one seems to work perfectly.  I tried a priest of a different race, and nothing runs when you use psychic scream.