Desktop mode is probably the least compromised, since I think (and this is gonna be pretty contentious) that the keyboard cover is actually a better keyboard than what's on the new MacBook, and the trackpad is about the closest I've seen a Windows machine be comparable to what Apple provides. While it might be a bit heavy as a tablet, it's just fine as a laptop.
Yes, it's basically a laptop with a touch-screen and semi-tablet OS over-layed. It should be a good laptop, within the constraints of hardware performance.
This is a fairy tale. Surface doesn't require pen for UI interaction. Having different input options is useful for different use cases such as when viewing/panning/zooming a Visio diagram touch is optimal, for working on Excel a keyboard with trackpoint or external mouse makes the most sense, for taking notes/drawing there's no substitute for pen (ever tried drawing with a trackpad or mouse? it's embarassing), for working in confined spaces like a flight the keyboard feels more premium and trackpad offers better palm rejection than Macbooks, etc. Switching to a Macbook after using something modern like a Surface feels like switching to a flintstone mobile that you have to peddle with your feet vs a car or in the case of iPad it's restrictive like switching to golf cart from car. I'm always trying to pan or zoom a document with touch then remember it's only a Macbook or stuck with blown up phone apps when needing to run professional software on the iPad. Two turkeys don't make an eagle.
Jobs made that comment in 2007 (like when the first real smart-phone was introduced, as limited as it was) and several years before the first iPad. Again, context is just a wee bit important. Do you remember the mobile devices of pre-2007?
And, I think you might be a bit mixed up, as the MacBook is a laptop running OS X (macOS), not blow-up phone apps. And, even the iPad doesn't run blow-up phone apps, unless you're just poking fun.
That said, yes, if I had to get serious work done, I'd probably pick a Surface over an iPad. That's because Apple made some really dumb decisions with iOS (which could easily be fixed if they got their heads on straight).
I spent nearly 2 years after the iPad 2 came out running only an iPad when mobile. It could be done, but wasn't optimal unless your work was limited (ex: a writer). But, it was also better at some things (ex: giving a presentation, or using on a flight/train). And, it was really good in small meetings (like meeting a client at a coffee shop) for note-taking without seeming too tech-intrusive.
With some of the advancements since in hardware and software, it would be far easier and more capable than it was with my iPad 2. But, for many jobs, still wouldn't cut it in terms of productivity. It's a trade-off you've got to be willing to make.
