Yeah, the thing that doesn't make sense to many of us is that 5e doesn't have a line of sight in the sense of characters looking in a specific direction. Its a stylized approach to speed up things by combining all your senses in 'Perception'.
Now one could say that vision should be limited, but when we realistically look at it our field of vision is 180° and not 45-60° as is the game. Also if we hear things, we can just turn our heads and eyes quite quickly.
I think Larian here has gamified the perception too much by taking a highly stylized/simplified perception system and further limited the NPCs by sight cones and mechanics that push things to absurd levels - as mentioned no sound or other senses + the option to lock enemies in place while 'stealthing' with no stealth skill while wearing heavy noisy armour.
Am I a fan of 5e's perception rules? Not really and as a DM even less. But changing an existing ruleset demands taking more into account as the rule itself. Larian doesn't pay enough attention to the collaterals of their homebrews.
Well said.
A mix of 360 perception and sight cones is my preferred solution. 60-90 degree sight cones of automatic detection combined with a hearing radius of stealth check vs perception detection. Has a little bit of both 5e RAW and Larian implementation, and doesn't completely ignore the relatively-core 5e rule that there is No Facing.
