[zaptheimpaler]

Do they really? Even on linux, I can look at what bandwidth a device is connected with using lsusb, but there is no way to tell if a low speed is a limitation of the device or the cable. It just displays the speed that was negotiated considering all factors. I've never found a way to get information about a cable digitally.

[luma]

There are a handful of dedicated devices that will read the eMarker, eg https://www.amazon.com/s?k=USB+emarker

A recent HN thread announcing a Mac app that can read them along with discussion on alternatives: https://news.ycombinator.com/item?id=47972511

[zaptheimpaler]

Very cool, thanks!