I feel many people underestimate how important visual cues are for the games. In tighter, more realistic games you can indicate the way foward with things like flickering lights, flash lights in the floor pointing to the right way, glowstick bread crump path or a million different thing.
But with large open world games, where player has freedom of travel its important for the players that they see with a quick glance if the wall is climbable or not.
For the game feel good players need clear rules how the world works. Red barrels explode, breaking this colour crate gives you loot, but these crates are indestructible, objects with this colour can be interactected with this tool etc.
I find it intresting when games have things like HUD on the screen and game highlights enemies and objects you can interact with people dont care about the immersion, but yellow paint is where they draw the line.
I remember reading how somebody hated how Resident Evil 7 marked everything breakable with yellow paint and how it ruined the immersion and made them remember they are playing a game. At the same time there is constantly visible ammo counter on the screen and you have radial wheel to change weapons and those things are not breaking the immersion at all.
