The first two are about the context you're in. What you're advocating is consistency of behaviour regardless of context and in those cases I kind of agree, mostly because I think the Ambiance switcher should die a horrible death. Left and right edge swipes should always go back to the multi-tasking view no matter where you are or perhaps left should go to multi-tasking, right to Ambiance or whatever it is replaced with (hint: a decent events view).

The third however is not an edge swipe, it's a swipe inside the screen boundaries. I've seen a number of people try my Jolla and before that the N9 and absolutely not get the difference between edge swipes and in-screen in-app swipes.

Dave999 for instance had no idea that you could edge swipe to accept or decline actions in-screen and instead was pressing the top corners while complaining about Sailfish's poor one handed support.

The UI requires a bit of re-learning but it's forgiving: you can half swipe something to see what it will do and then swipe it back if you don't like what it does. You can delete stuff and then tap the remorse timer coutdown if you made a mistake. That's a great idea compared to tapping on cryptic icons and endless Are you sure? dialogs in the other mobile UIs.