alt Hacker NewsFor the Duo to make sense at all, it basically has to fold out into a screen which is big enough that (quite often, at least) you don't feel obliged to bring along a second, larger device anyway, or to wait until you get home or back to the office to "do real computer". That means that hitting a large-enough unfolded size and a suitable unfolded aspect ratio had to be Priority 1.
That's not really why foldables make sense. It's not for productivity, primarily, it's for entertainment. Videos and ebooks (and other long form text content) look better and feel better on a foldable (for the same reason we have e-readers despite having Kindle apps). Multitasking I'll admit is more useful on mobile now in the AI era than in the past. But really, a foldable isn't meant to compete with a Mac Air or similar. I don't even think it's really competition for iPads. It is nice to have the optionality and flexibility at all times and nothing is more on your person than your primary phone.