I live in the sticks and internet connection at home sucks to say the least.
Downloading something like a chroma file for a color DMD is fine, but a larger downloads like code updates are basically impossible. For that I basically take a usb drive to work and download it at the office.
If a newer pinball machine was only able to be updated by direct download via WiFi I would not buy that machine.
It would be fine if you could do it via WiFi or usb, but it it was only WiFi I would not want it.