With the recent 1.1 patch, Aim Assist is now present for PC players and has no way to be turned off. I believe people on all platforms though would appreciate being able to turn it off so we can do all the aiming with no game help.
I absolutely want this disabled for PC. It's causing people to aim towards players sometimes when fighting NPCs. It's also favoring body shots, which makes aiming for headshots more difficult. Also, any kind of auto-aiming is a ridiculous notion for the PC