[hffftz]

> If you want to add usb, you buy an extra chip.

Do you know how many chips are in a cable modem/router combo?

[formerly_proven]

1 or 2, depends on the kind of modem. VDSL2+ modems might have three, though one of those is the line driver which is zero-delay for the purposes of a computer.

[hffftz]

I've seen many more chips last time I opened one....

[jaywalk]

Most of those chips have zero impact on latency, and many aren't even involved in the actual packet flow.

[ben-schaaf]

Modems/routers don't use polling nor do they need debouncing. The default USB polling rate is 125Hz, which is already 8ms of latency. Debouncing depends on the switch and is generally a couple milliseconds as well.