not against networked printing, never said I was :-)
As long as it's implemented properly - ie: not streamed across a network.
And as you're not printing directly over the network - there isn't going to be any issue :-)

Your original question was unclear.

Only mentioned a serial interface, not whether that was on the board itself or via the usb interface (yes I know it stands for: universal serial bus) but generally a serial interface is still considered to be something quite different. Although most devices using serial interface do use a simulated port over usb. It wouldn't surprise me if there was a traditional serial port on a raspberry pi. No, I can't be arsed to go find out.

so go on, what phone ?