OP here, it's true that these monitors are fine. 'Dead' was due to title text limit, as I had originally wanted to use 'unusable'.
Buy a Macbook Pro and you only have USB-C ports for connecting other monitors and peripherals, and Apple currently don't make a 1st party hub. Whilst you can go USB-C -> DisplayPort Alt Mode, this means multiple cables and doesn't solve other peripherals and power. So many people have adopted hubs like Dells D6000 which is actually a pretty great piece of kit, and lets (or used to at least) any USB-C capable machine (Mac/Linux/Win) be plugged in with one cable and get multiple displays, ethernet, usb, headphones and power all from one little plug. It was awesome!
DisplayLink may have started off as a lowly USB display standard, but it now can support multiple 4k displays at 60hz which is pretty impressive, and has been working perfectly fine for quite some time across plenty of different devices and monitors.