What's so great about the Surface Studio other than its touch (for those that want touch on a desktop). My understanding is the parts aren't really any better than what Apple is offering in the iMac. And it's expensive. So is it just that you can use it like a drafting table? That seems to be to be a niche of a niche market.
Well. The iMac is also only covering a niche market -- the fact that it runs macOS instead of the industry standard alone doesn't help much to get it out of a niche.
That being said, the Surface Studio does run the "industry standard" desktop platform, allowing it to run any application on the market and allowing it to be used for any purpose, and ON TOP OF THAT, it is also a great solution for people who can take advantage of its capability to be used as a drawing board. (Just as an anecdote, the head of my company's networking department would kill for this machine -- he's nuts for every electronic device that he can use to draw network diagrams by hand. He usually does this on his Galaxy Note...) Sure, not everybody needs or wants that. But not everybody wants or needs an all-in-one machine either.
It's expensive? For what it actually offers, really? That's quite debatable. However, Microsoft isn't trying to attract the mass market here, nor are they trying to beat their OEM customers. The Surface Studio is first and foremost a reference hardware that is supposed to show off features of Windows 10 that NO COMPETING PLATFORM has. You simply cannot do this with macOS -- using an external tablet for this purpose just isn't the same thing, no matter how much you might want it to be. Nor can you properly do this with any Linux distribution or FreeBSD or Solaris or whatever else you may find on the market. Yes, you can pull an Android or iOS gadget out of nowhere - but those aren't desktop platforms, and they don't have that caliber of application software that Windows has.
So, no -- Microsoft isn't delusional about the Surface Studio
itself becoming the ultimate market leader. However, the Surface Studio shows off Windows technology, and it's supposed to inspire OEMs to build similar (and usually more affordable) machines - and the sum of those third party devices might eventually become a leading standard.
This is the business Microsoft is in. (Or Google, for that matter -- their Pixel devices are high-end reference implementations, just like their Nexus devices were reference hardware for developers. There never was any intention to be the market leader in hardware.)