My x86_64 laptop uses a 50-watt charger, and even I wish that it could trickle-charge through its 5-volt usb-c port, but it can’t. I wouldn’t consider this a problem because the dedicated power port is a barrel jack, but if there is another pinebook revision then supporting 20-volt, 5-amp usb-c charging instead of coming with a charger would be super awesome, and make the product even cheaper.
I haven’t had issues charging my PBP with USB-C. I don’t have an nvme drive in, but it does charge fine. Just very slowly. It’s a limitation of the battery controller it has.
So if the PBP has load while charging, it actually uses more power than it can charge, even with the barrel charger.