It's totally pointless, because the trackpad is already a touch device... and you use it to manipulate a precise cursor that doesn't block your view of what you're working on.
Except that the trackpad has to be used to get the cursor all the way over to the control --- it's often faster to just reach out and touch, and if using a stylus, then the cursor goes right back to where the other hand was working as soon as one lowers it back into hover range.
And requires a LOT less effort too. There simply is no real benefit to a touchscreen on a laptop. It’s ridiculous. It’s the phablet of laptops. Insane.
I find it lends a lot to the flexibility of the device --- but I'm using a touchscreen on a convertible which I can flatten out into a tablet w/ keyboard to one side or the other, or fully reverse into an expansive tablet.