The touchbar as a design decision makes a lot more sense when the brief is "Add touch to the Macbook Pro line... but under no circumstances step on the toes of the iPad Pro"
The OS would need an interaction overhaul to make it work with touch - the hit targets are all the wrong size and a lot of behaviour relies on hovering over something. Couple that with the fact that the screen is at the wrong angle (I find it makes my arm ache just using an iPad with a keyboard and having to reach over to touch the screen) and I think Apple aren't too far wrong.
However, as someone who likes drawing, the way the Surface Studio folds down to an angle that is better for touch and pen does look pretty good to me.
I think it's more that retrofitting touch to a desktop OS - any desktop OS - is painful. Microsoft started it with Windows 8 and it's nearly - but not completely - done years later with Windows 10.
I suspect Apple has probably started retrofitting OS X privately, but released the touch bar as an interim solution.
It frustrates me that almost every Windows laptop with a nice screen is now touch. I assume you can turn it off, but you do pay more for a touch screen. This just reenforces my (outdated?) notion that it's a consumer, not professional device.
As a power user, you probably use the keyboard most of the time and occasionaly a single mouse operation (like moving focus somewhere). For that, it's quite intuitive to tap.
As someone who's just started researching to buy my next laptop, I don't find that to be very true at all unless you're only looking at ultrabooks.
One of my almost-gotta-haves is a touch screen, and for any models with an HQ/HK level processor plus a discrete GPU, there only seem to be a handful of models with touch screens (and when they are there they are usually optional) at the highest end configurations.
For me, touchscreens are perfectly useful on laptops, since directly tapping something is much quicker than moving my hand to the trackpad, locating the cursor, moving it around and finally clicking something.