I mainly do all that stuff just to be cool. Like I said, its a power fantasy, rigorously calibrated and playtested to be accessible to millions of people.
You also touch on why the higher difficulties in UC never really interested me before. Its the same thing, but more tedious with enemies given more health/you less health. It goes against the whole power fantasy narrative I primarily play these games for, and whats clearly the developers intent for creating them.
I think TLOU is really quite brilliant in making a survival horror game thats still built to be accessible to a lot of people. Where in UC where you get in a fight with somebody, you'll win all the fights and any damage that happen you can just hide behind a wall and it goes away. In TLOU, even if you DO win a melee battle(and you often won't!), that damage sticks with you. Your supplies drop. Now you got 2/5th life left, 3 bullets with a shaky aim, a brick, no medkits, and you have no idea where the enemies are.
And like I said, its not really UC's fault that it cant be as good as TLOU. Its simply how its formula is calibrated to be this popcorn matinee adventure. Its breezy pop insubstantial status is built into its gears.