A lot of those streaming sticks will draw huge amounts of current for the graphics hardware. Everything will be fine until the graphics gets turned on. If you can’t deliver enough power for that, they will brown out – only needs to be briefly – and crash/reboot.
Big capacitors to mitigate this cost $$$.
Look at all the threads about power supplies for a raspberry pi – they have similar problems (but it’s derived from a mobile chipset, so power draw is at the lower end).
I’m not a hardware engineer, but I have spent a reasonable amount of my time on this planet debugging boards that reboot due to shaky power supplies.