And how does any of this map to, "You've arrived at a vista, make a perception check so I can tell you more things?"
Passive perception is due to repeated actions -- it's the average value of multiple checks. It's not an innate ability to see things, but rather the result of a continuous action declared by the player for the PC. "I'm watching for traps," is the declared action, which you are resolving with passive perception. This can be improved by the player in myriad ways, and they are likely to do so because the situation is one in which traps are expected, so maybe they have a light source instead of relying on darkvision.
I think my preference is to make them roll if there is a risk and if there isn’t risk not make them roll and let that speed up play. I agree that asking players to knock their head against mundane tasks is fairly boring. Though it’s very rare that I set DCs higher than 20 - 25 anyway so taking 20 would be a very great boon. I think 5e has the balance about right as you say.Or it might be that it's actually a good mechanic that speeds up play a lot and take some unnecessary hassle out of skills resolution. That's my take on it, even though 4e and 5e did not follow suit (I'm sure about 5e and pretty sure about 4e). But 5e has even better, automatic success or failure.
Why ? Just for the pleasure of rolling the dice ? Of frustrating the players ? It's not a roll-playing game.
Or it serves to make exploration story-driven rather than more random. Again, YCMV and to each his own, I can understand both ways of wanting to play the game.
It works for a lot of us, you know, it's about role-playing, the character might have thought about bringing something that the player did not know about. I don't have to be a wizard to play one, which is a good thing. And I have better things to do than to list extra pairs of socks on my character sheet, for example.
Again, it's a question of style of play, both are valid, calling one "cheating" is not going to make the discussion go better.
And this is probably one of the reasons for the different opinions above, I enjoy exploration, but like roleplaying even more in general.
You're still ignoring the second example, wherein the DM is offering information freely. Maybe instead of saying the trees are withered, the DM says they see something glinting in the forest below. This does offer the players a choice. They can ignore the glinting and continue on, or step off the path and investigate.
The latter isn't anything different though -- the player has declared actions that indicate that their character is on the lookout for monsters, the passive check is just a way to resolve that result "secretly." If the player had declared an action that prevents noticing the monster, passive checks wouldn't matter. They only apply to situations where the event is something the PC is trying to do because of player action declarations and the GM elects to resolve this "secretly." It's not categorically different in the manner I'm discussing.
Of course they matter, but this doesn't give the GM the ability to puppet the PCs. The matter when the player declares actions and the GM elects to resolve those actions using the mechanics of the game.
Because I don't have issue with free offers of information because they do prod for action declarations. Are you abandoning the first example, then?
