Sorry, no! The RP2350 has a builtin USB 2.0 controller. The additional contacts of USB3 will never reach the MCU.
Your observation regarding stable power is of course true, but keep in mind this is a microcontroller that does not draw a lot of power, so the power-requirements are very low - as long as you don’t attach a lot of peripherals, which you shouldn’t anyway when you are flashing.