This reminds me there was a time when affordances were all the rage in UI (early Iphone) and Steve Jobs was a fan, wonder if we get that back at some point.
Probably. As with pixel art or design that mimics the early WWW era, it will become part of some retro hype cycle.
I think a lot of these trends come in waves, so in time flat UI will hopefully fade away and we'll get slightly chonkier UI elements that are (IMO) a little more discoverable and user-friendly.