At the moment some of those competitors may have spare supply because people weren’t interested in them before. But once that runs out, I don’t see a reason they won’t all run into the same problems as the RPi Foundation as they get in line behind them for the limited-available time at the fabs.
* Performance garbage, single core, very cardy to use
* Some software porting risc-v has wonderful bugs
* No GPU, very laggy
and really nothing exciting on arm. I'm expecting these to disappear soon as well. really hoping some fab time opens soon to get even the allwinner devices back on the market at reasonable price/quantity.
Why do you think they will be supply constrained? Does Allwinner make Rockchips?
I see the competitors being a bit more flexible in regard to SoC used. There seems to be a plethora to choose from with different chips, but I am speaking from a very lay person POV.