No, it's the difference between wanting to use an axe that has a 50% chance of doing 100 damage and a sword that has a 100% chance chance of 50 damage, then being asked to hit a guy with 75 health.
That is still how the game works. All weapons have a max and min damage, and even more there is always a chance of crit. So not sure, what you are trying to prove with that argument.
Also it not RNG, it is chances. It is part of the tactical gameplay to change the battlefield situation, so that the odds are in your favor, and not in your enemies. If there is no risk, there is also no tension, making fights just long lasting and boring, easily calculatable.
Anyhow D:OS2 is about armor management, not about life management. It is only life management if you failed with armor management. Because if your armors are gone, you are getting CCed.