I can't imagine trying to do that on an iPhone. Surely it's useless.
What this does do is reveal the fiction that "iPadOS" and "iOS" are separate. Clearly not.
Just as a N=1, I would rather pay a recurring fee in the Disney-Netflix range to Apple to get more liberty in usage from my machines. But I think they don’t dare to go those routes, because they need the broad market base and cannot extract the current cash flow from a smaller base, while setting expectations that the Googles, Samsungs can copy.
Industry leaders dilemma. Apple currently settles on market differentiation via physical products.
Only for the truly low end. The thermals alone are a serious difference, you can't expect an iPad-class device to support the same power dissipation as a legit MacBook.
They're not doing it today because current Apple leadership doesn't have the same incisiveness as the one back when they were sacrificing their most successful product on the iPhone altar so the competition can't. And to be fair, Apple has a much stronger position with a wider moat then they did back then. So they can afford to give more time to the competition to compete.
Apple wouldn't just sacrifice the entry-level MacBook product category and I'm not even sure about that - the look-and-feel of a "display with attached keyboard" (i.e. Thinkpax X1 Tablet-style) is vastly different from a bottom-heavy Macbook with actual hinges. The former isn't really usable as a literal laptop unless you got some seriously long upper legs.
The more important thing that Apple would have to sacrifice is the App Store cash cow and users not having root rights. On a iPad or iPhone I'm willing to accept that, but on a machine I actually want to do work? No way in hell.
The iPad Pro with Magic Keyboard is just that and in my personal experience does very well even on shorter legs due to its weight distribution. Were Apple to go down the route of actually enabling Xcode, etc. on iPads, they'd likely invest a bit more into the ergonomics of course, but they are already there and not comparable to Lenovos efforts in that regard.
Xcode is huge, it’s bigger than most games. A lot of that size, is an aggregation of tools, built up over a couple of decades.
Replacing it with a rewrite, would be a major operation, but would probably be required, in order to work on iPad.
I suspect there are dozens of tools, that are years old, have very few folks that know how they work, and probably only work on Mac.