What's the use case? Where do you have a display, keyboard and mouse but no computer attached and no laptop at hand?

I never have this problem where I'd want to blow up my phone onto a bigger screen (with full mouse-based editing capabilities). But I guess it might be more common than I imagine.

When I look at what I was doing with a computer in 1993, and what I mostly want to do with a computer today, it should be really easy to do with a phone.

It's kind of weird to me that my phone is so massively powerful but gets used only for a bit of web-browsing and light game playing.

It doesn't feel like a 21st century solution.

But does that mean you should do everything on your phone?

The 1993 computer probably cost at least 2000 USD. Today, you can get a phone, a laptop, a desktop computer, a tablet and a smartwatch for less than that. That's five devices with different form factors!

Is there really a group of users whose single device is a phone and they want to connect that to PC-style peripherals?