It may be worth mentioning tweaking the BIOS settings to "Other OS" if its set to Windows 10 WHQL or Windows 10 NON-WHQL depending on the BIOS type. Are you also confident the USB thumb drive isn't.. hmm.. malfunctioning? I'm fairly confident based on what you've written that you've likely tried more than one, so this is very strange. If it were a widespread issue I am fairly confident it would be all over the place.
Also make sure everything is set to legacy compatibility instead of UEFI-only in the BIOS if you can.