> Just because Marzipan/UIKit today doesn't have good MacOS affordances doesn't mean it won't in the future, especially since it's not even being offered to developers right now. I don't see why it's difficult to see where the puck is going here.
It's not difficult to see where it's going. I just think people are believing it's going where they'd like to see it, where they think it's best for it to go; whereas Apple has their own ideas and always has. What we think is better for the ecosystem, they mightn't see it that way; what we see as the natural course of things, they might see as a passing fad.
Plus, we look at Microsoft's attempts at this very task with Windows 8 through 10. Seems to be a bit rough going. Apple famously accused Redmond of starting their photocopiers; I'm not sure Cupertino's Xeroxes are even close to warming up on this front.
Plus, it reads just a little too optimistic for me. We are already seeing that sharing user interface code between desktop and mobile results either in crippled experiences on both or each platform requiring its own platform-specific user interface code anyway. Instead of one amazing app on two platform, you get two crappy apps that feel like they belong on the other. In my mind, the poster child for this is Discord - it works well enough until you want to do some basic management, then the desktop version is pretty much mandatory.
If you're right about Marzipan having different UX affordances, I think Apple made a huge cock-up by demonstrating apps like Home. On a Mac, Home is an awful mess; the most basic operations are made unnecessarily difficult, what would be a long press or force touch now becomes an irritating secondary click (which is most annoying because I have a Force Touch trackpad not doing anything useful). Even the App Store is missing so many macOS features by virtue of being a Marzipan app.
I'm __hoping__ these are just examples of Apple eating their own dogfood, knowing it tastes terrible. But I'm just having terrible flashbacks to when Finder was a Carbon app and performed like a dog --- oh, that's where the dogfood analogy comes in, I guess!
That said, I still don't think Marzipan will be a convergence. I believe it's a stopgap. macOS is still the truck compared to iOS devices' cars; you just can't drive a truck using a car engine.