I find that quote odd too. I find the $10 USB-only ones useful, I just wish they had dual normal/micro USB like some flash sticks. I don't want Bluetooth, NFC

I find that quote odd too. I find the $10 USB-only ones useful, I just wish they had dual normal/micro USB like some flash sticks. I don't want Bluetooth, NFC or software u2f devices for security reasons, but I also think they could each have additional support problems if given to family members. The ideal option for me would be an applet on a smartcard in my phone's 2nd sim bay and a hard power toggle for the 2nd bay. Then I suppose my phone could also provide proxying of u2f as a USB device. But last I looked Android was blocking access to simcard slots for general purpose..