Great question..

Me personally? Nothing. I hate them. I never want anybody to touch my screen.

However, I've talked to at least one team that has disabled their app on MacOS who thinks having a UI designed for touch-screen run via a trackpad is too janky and would lead to a bad UX for their customers.

I've run their app via playcover, and it IS janky, but its a lot better than the weight of an iPad in my backpack.

They're inherently convenient and fast to use. As I'm typing, it's far more ergonomic to take my middle finger and swipe on the screen to scroll than to reposition my hand to have two fingers on the trackpad. For extended reading I can keep one hand at the edge of the screen to scroll with a thumb instead of cramping my wrist. Zooming is quickly and intuitively obvious rather than having to figure out where my mouse cursor is, reposition it, do a pinch gesture or Ctrl plus (where IS the plus key? It seems to vary on every laptop I own), etc.

not the person you're responding too, but I'm writing this on an older ThinkPad L390 Yoga with touchscreen, and I gotta say, being able to scroll on the screen when reading large documents (like PDF textbooks), or to just touch the part of the screen you'd like you're cursor to be if you've got multiple windows open is really nice.

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