As a recent Android foldable phone owner (Google Pixel), I'm excited that the Duo will get developers to actually design apps for foldables. Right now, some apps don't work at all and others are just stretched. I feel a better use of the screen space is around the corner for both Android foldable and Duo users.
It would depend on the sales volume. For a long time the iPad has been available and many developers simply are content to have a stretched version of their iPhone app on their iPad, because the sales volume isn’t sufficient. If foldable phones sell like iPads, this could very well happen to them too.
I think they need to aggressively court developers, just give a buttload of advertising credit to nice apps that predate AI slop if they add compatibility, what does it cost Apple to "give" you $10k or $20k credit in their own ad system...
But the rumours also say they are going to squeeze the App Store for higher margins so maybe it is too late.