What makes it not-phone-capable? The non-s variant powers the "open source laptop" that was on the front page a couple of days ago: https://news.ycombinator.com/item?id=42797260

Power profile. The SoC will need more space for battery and cooling that's physically possible in the smartphone formfactor.

At full speed sure, but if they use the metal chassis as a heatsink and downclock it a bit it ought to be fine, right? There are rk3588 SBCs sold without any heatsink at all (and I'm sure that does result in throttling, but presumably it's manageable)

Not sure but gonna guess power.