Too many bugs that they wont fix anytime soon.
Explosions go right through walls no matter what killing you even if it's something a grenade couldnt even get through.
Hiding spots dont work because if you try to peak from the edge of the wall the enemy can see you before you're even able to see them at all.
Ontop of that running behind cover doesnt really work because they can shoot you when you think you're behind the wall similar to before.