ah, i see. in that case i can't say i agree. i'd say that it's fairly predictable - i can't think of a single app with a drawer in which it didn't work, until they introduced gesture navigation and broke it.
with a back button, it's always in the same corner; with a back gesture what happens when the phone is rotated? (i genuinely don't know) does it stay on the side it was on, or does it move so it's now on the left? wouldn't that make it very hard to reach with one hand?
A swipe from the edge to open a side sheet has a trigger area that extends far beyond the confines of the Hamburger Icon.
yes, but it doesn't extend beyond the confines of the drawer. in my head it's more like the drawer is always there, and you can trigger it with the hamburger, or "drag" it into view manually
And if any of the other gestures are present, then the edge gesture conflicts with them.
not really - one is from the edge, one is not. it doesn't conflict any more than scrolling up conflicts with the new home gesture (and is far less often accidentally triggered)
Even worse is, the gesture with no visible area is “on top” of the others that have a predictable area, despite the fact that they exist on the “same plane”.
that is reasonable. i can't say anything to refute that
Like, with the edge gesture to open a drawer, you need to keep the app elements in mind as if there is some physical elevation inside the app. The edge gesture is on top of the tab gesture, and things like that
i mean yeah, that's the very point of material design. the whole spec goes on and on about the information conveyed by implied depth
but even before that, drawers and menus usually had some type of drop shadow to imply depth (practical skeuomorphism at work^!^)
With the system gesture, the elevation itself is between the app and the system. Almost like if the system gestures are a glass panel on top of the app. It is a predictable rule.
yeah, i subjectively don't like that. with nav buttons and a status bar, that's where the system was and that's how you interact with it. now it's an invisible layer over the whole screen that's not predictable at all; as a swipe right goes back, but a diagonal swipe does something else. that's two gestures on the same metaphorical "layer", one a system action and one an app action. weird.