About this, my point is that if the character passsed both of the DC and beating every monster's Passive Perception with their PP potentially raise up 5, at lower levels or lower Stealth, but somehow luckily passed it, then just narrate it luckily, as it actually happened in the reality (since DM didn't consider players can't Hide). This is not impossible both in the narration or in reality. It could be the enemies were distracted by a bird or simply having a yawn.
No. Sorry, but I’m not going to do that. I don’t think that’s an acceptable narrative restriction to force on DMs. And any rule that allows a character to remain unseen while completely out in the open for an indefinite amount of time is, in my opinion, a terrible rule. I understand that since D&D doesn’t have rules for facing, there needs to be a way for characters to move from one hiding spot to another without being seen, or to remain hidden long enough to make a melee attack. But that can be done without also enabling characters to spend several turns, minutes, or even hours completely out in the open doing whatever they please short of attacking and still not be seen. Simply saying that you stop being hidden from a creature if you end your turn without cover or obscuration from that creature and both problems are solved.
On the other hand, I always think 5e made it impossible which was more...too gamey?
The pre-revision 5e did
not always make it impossible. It was impossible by default, and the DM could rule that it was possible depending on circumstances, such as the target being distracted. That worked fine for me, but I understand it didn’t work for some folks, especially because some DMs would just never rule that it was possible. I understand the desire for a way to move between hiding places or run up and make a sneak attack without relying on DM fiat, and agree that would be a positive change. But you’re proposing the opposite: that it’s always possible to remain unseen without cover by default, and the DM
must use fiat to ever rule that it isn’t, and that’s not any better. It is, in my opinion, far worse, because it requires the DM to make a ruling that is
more restrictive than the default rather than less, which always carries the risk of being a controversial ruling. There needs to be a middle ground, and I think that being able to remain hidden as long as you
end your turn with the criteria to hide met is a solution that would satisfy all parties.