You can use Dvorak regardless of what letters are printed on the keycaps.
With that said, having Dvorak keys on my laptop would make the keyboard unusable or very difficult to use for a large number of other people, and so even if one were offered, I'd be unlikely to buy it. Even for many people who touch type well, I think having keycaps that are wrong when one does glance at them is something that takes some experience to get used to, and a Dvorak user typically has that experience, whereas a Qwerty user usually doesn't.
Even when keycaps have uniform profile, the 'F' and 'J' keycaps will often have bumps on them. These are the 'homing keys', so that it's easier for the fingers to return to home row.
If somebody who only knows qwerty uses your computer, you should switch the keymap to qwerty for them, not force them to try to navigate an unfamiliar layout. Every major OS makes it very easy to switch keymaps.
I'd suggest learning a new layout is easier on an entirely different keyboard, so as to minimize confusing the fingers' motor memory.
> who only knows qwerty has to use your computer for whatever reason they can still hunt and peck vs it being completely impossible.
Hunting for keys on an unfamiliar layout is impractical.
In my experience, just switch the layout from Dvorak to US International, if you're using Dvorak and someone else wants to use your laptop.