Deus Ex gives you points for achieving objectives, and not for hacking panels and shooting guards.
Meanwhile, both DX:HR and Cyberpunk 2077 gives you XP every time you fart.
One effect of this is remaking the old DnD anecdote "I need 5xp to level up. How much XP is that cow in the field?" chop
In DX:HR, I ended up hacking every alarm pannel even if they posed no threat for me as I had already given every guard in the local metropolitan area the gentle snooze hug. It's free XP, baby. Similarly, in Cyberpunk, I sometimes manually disable cameras for Engineer XP.
It also enforces gameplay styles.
In the original Deus Ex, you get XP for the objective, no matter if you achieved it via stealth, hacking, or indiscriminate violence. The real fallout is in characters reacting to your actions.
In Human Revolution, being the stealth sleep-spreader nets you 200 xp vs. going guns blazing.
This is not the same as the player chosing to go non-lethal because JC's brother Paul urged them to or they have an aversion to killing.
I don't know if it's as borked in Cyberpunk 2077 - if anything, it doesn't reward stealth enough and hacking straight up sucks - but it would also be better if you couldn't farm XP by being stealth Hypnos hacker.