Enemy footstep sounds are a joke, not speaking of dead silence field upgrade which makes footsteps from barely hearably to non-existant.
Players can whitstand 8-10 bullets without any particular damage and even shoot back like nothing happened. Headshots also do ridiculously low amount of damage. Even if you somehow manage to 'DOWN' someone in a highly randomised like 50-50 face-to-face fight, after landing those 8-10 shots you just DOWN your enemy. At this point they are not dead, can crawl around and can be revived by teammates of with a self revive kit. Even a downed enemy requires the same amount of 8-10 shots to FINNALLY kill them. (I mean send to the Gulag where they again have a chance to respawn :D, or even when this last resort fails, your teammates have a chance to buy you back, after you've already been killed 3 times)
Very huge percent of the playerbase is cheating and devs do not even care.
There are pay-to-win weapons which you can buy with your real money in order to do higher amount of damage thanks to the instant unlock of by default locked weapons and attachments.
And for the last, I don't know why this game wears the name 'Call of Duty'. It is not even close to a COD game, there is nothing COD about is, but since it has the name, I can say it is FAR-FAR THE WORST CALL OF DUTY I'VE EVER PLAYED - starting from Call of Duty (2003)