The point of playing a non lethal style is the same of all other gimmicks that are in the game.
The only thing is to complete some missions. There is no moral code, humanity, or some personal moral values in the game that makes it trully relevant.
Just like nudity, romance "options" (that are only one, or two if your V is bissexual), most of side activities, restaurants, bars, even drug dealers (that sell the same products as the pharmacies).
All of those are in the game, but have no gameplay effects on them. You can be naked, but can't run naked in city, and if you go with female V boobs out, what will happen? Nothing. Why? Because nudity is in the game because some fans requested, not because it was a part of some artistic vision.
Why restaurants, bars, night clubs and food machines are there? For nothing. Food have a very mild effect. There's no character animations linked to them.
Well, how about dancing? It's there too, but serves nothing.
Swim? Yes, it's there, but even the water has no physics and can't be affected, even grenade produces flames and explodes just like when there's no water.
Relevant choices? Gimmick
Pacifica? Gimmick
Police system? Gimmick
Gangs with proper lore and story? Gimmick
Physics? Gimmick
Collision system? Gimmick
Water? Gimmick
All those are there just to integrate the scenario. But most of them are irrelevant to the gameplay, it's an unbalanced version of The Division 2 with Deus Ex visuals with some jig jig street sprinkle on it.
It would be better if this was just a linear game, with the main missions only, like Deus Ex, with no fake promisses and without the collection of empty gimmicks.