My recollection from previous queries about this was that PoE was considered too fringe to merit the additional effort. It would complicate the PS design, since you have to convert from 48VDC or 24VDC.

You are probably right. Since it is a fringe feature, it would probably raise the cost quite a bit.

I was thinking it would be great to have a network of these as remote sensors, or to distribute synchronized video or audio. Instead it of it being powered via the USB interface it would provide enough power via PoE to power other USB devices.