Should Passive Perception be lower?

Quote from SunIsGettingRealLow96589 >>

 Its not that its harder for monsters ot percieve you,  It's harder for you to hide.

You can think of the minimum DC 15 on the stealth check as a minimum passive perception that all creatures have as far as your ability to HIDE is concerned. 

Yes, that's exactly correct.  This was an intentional change and it's functioning as intended.

Quote from SunIsGettingRealLow96589 >>

No. Your perception is not positively affected during combat.

This is the very root of the problem.  During combat you get tunnel vision. You get hyper focused on the threat directly in front of you that you don't see the guy coming at you 45 degrees to the right. Studies repeatedly show this.

. . .

Civilians are absolute garbage in combat. They panic. They freeze. They do stupid stuff.  One of the goals of military training is to transform civilians into people who can get some modicum of functionality under combat conditions. The military trains and trains people for combat so that they don't compeletely freak out during combat.

So, during combat, unless you're taking teh Search Action on your turn, you get a -5 penalty to your passive perception for disadvantage. 

 

It is an assumption of the game that individuals who become adventurers with a Level and Class have gone through quite a bit of training and in most cases have extraordinary and borderline heroic natural gifts and abilities as evidenced by how the standard rules do not give PCs a 10 in every stat.  They are not "civilians".  They are adventurers.

The 2014 rules explicitly stated that creatures have 360-degree awareness during combat.  When carried forward to 2024, this exact phrasing was dropped as a blanket statement just in case a DM needs to make a ruling about some unusual circumstance.  But this concept of creatures being aware of the battlefield is baked into the rules for combat all over the place.  If you want something more granular and grittier then maybe some other TTRPG system would be a better choice.  Certain things like this are simplified in this game for several decent game design reasons.

Not only that, but anyone who has played team sports, particularly those which require a combination of focused vision and peripheral vision such as soccer or ice hockey or basketball will disagree with your description of "tunnel vision" or "panic" under pressure pretty vehemently.  In my experience when I am engaged in such activities I can see and hear the environment around me way better than I can when I am laying on the couch vegging out and watching TV, or even when I am at my workstation in front of a computer.  Senses are heightened, reflexes are faster, mental and physical abilities improve and so on during such activities as compared to the rest of daily life.

The numbers that are listed in the hundreds of stat blocks for all of the monsters in the game are really meant to be used as they are listed to find hidden creatures both within and outside of combat.  That's the entire purpose of it.  There is absolutely no reason to impose disadvantage on perception just for being "in combat".    On the contrary, as Pantagruel666 suggested earlier, I would be more inclined to grant advantage as the default while "in combat" instead.

Just think about these two basic scenarios in real life.  You are walking down a path that is lined with trees.  In the first case, someone is hiding behind the trees.  In the second case, someone is standing in front of you on the path.  They scream out a war cry and then they throw a water balloon at you.  THEN they run to the side of the road and duck behind the trees to try to "hide".  Which one of these people behind the trees do you think you are more likely to see?

Quote from Pantagruel666 >>

While it's true that people get tunnel vision in combat... 

And yet, even if you get tunnel vision in combat while you are distracted attacking things trying to kill you, dnd rules say your passive perception is as if you had a completely average roll from taking the Search Action for a Perception check.

(A) Youre in a room by yourself, nothing trying to kill you, all the time in the world looking for that hidden lever that opens the hidden door.

(B) mid combat, surrounded by monsters all trying to kill you, and all your actions have been focused on killing them.

In current rules, both A and B will get the same perception, on average. And half the time (A) will actually produce a worse score than (B).

A and B getting same score on average is not getting tunnel vision in combat. And the fact that half the time, actually spending time  searching produces a worse result than just attacking is bonkers.

If you get tunnel vision in combat, there should be a penalty to passive perception.  And id suggest that Martial classes eventually get features to counter that penalty.   

"It is an assumption of the game that individuals who become adventurers with a Level and Class have gone through quite a bit of training and in most cases have extraordinary and borderline heroic natural gifts"

You usually start out level 1 with the hitpoints of an average commoner. Level 1 characters can die falling out of an apple tree. And while there are backgrounds like "soldier" and "guard", you start level 1 the same as anyone. Those backgrounds gave you a skill proficiency or two, and different starting equipment.

Its also a common trope to get a player who wrote a backstory for their character that puts them at legendary status. They already slayed a dragon, somehow. They already saved  their village from an Aboleth, somehow.  Nope. Sorry. You start at level 1, like everyone else. Anything legendary about you is in your future, resulting from how you play in the game. If you just want to write a legendary backstory, write a novel. 

Quote from SunIsGettingRealLow96589 >>

And yet, even if you get tunnel vision in combat while you are distracted attacking things trying to kill you, dnd rules say your passive perception is as if you had a completely average roll from taking the Search Action for a Perception check.

 Nothing in the rules says that you get your passive perception for finding secret doors in combat. You get your passive perception to spot people using stealth.