The points at which the game transition between acts seem a bit arbitrary (mainly for Act I to Act II), and I don’t see a narrative or mechanical reason to lock us out of previous maps and quests. As far as I remember, previous Baldur’s Gate games didn’t have this kind of points of no return. Why do you think they did it? Do you like it?
When I’m running a game I absolutely tell my players things that I think their characters would be aware of, and that includes time pressures that a reasonable adventuring party would understand through professional experience
They do give you hints with some of them - I did a long rest and everyone was telling me we needed to hurry or the dude trapped under rubble was going to die. I thought that was a good way to handle it.
Exactly, all the time critical events I encountered had NPCs clearly indicating it’s a time sensitive issue.