Treyarch has now updated Call of Duty: Black Ops 4 and made a ton of changes and adjustments to the game in the process. Probably the most desired change was making armour less effective, which has been a huge problem mainly in Blackout as it's so thick that it makes battles unfair where shots to the body are like trying to kill someone by throwing marshmallows.
They have also adjusted the spawns and footsteps are also easier to hear so you'll know if someone else is sneaking around in the same building as you. The studio also writes that the "weapon ecosystem is in a healthy state since launch. We have not seen a standout "best" weapon in each class, and every weapon found a strong player base", although it has adjusted the SMG to make them somewhat better.