USB-PD to power a DAC?

I am planning to build a DAC with TPS7A47/33 combo for the +- rails of the output stage. (for reference, this would be my second diy DAC and my first with a proper external output stage). I have some experience building devices powered by USB-PD, and was thinking.... wouldn't it be easier to just use the 20V the USB can give me and take that directly to the TPSs and then go down buck/LDO to the rest?
I could not find many comments on USB-PD powered DACs, is there anything i am overseeing?
thanks!