Finally got betrayed by USB-C. Our crafting laptop, a Lenovo L3, has a USB-C port on it which is adamant that it is not Thunderbolt. It is newer than my Thinkpad T480 which has 2 USB-C ports, at least one of which will do Thunderbolt and I believe both do DP Alt Mode too. But our crafting laptop is newer and fancier and has a CPU that's a couple of generations newer, etc. etc. etc.
My partner uses the laptop for streaming and is about to get a work laptop for her new job, so we went out and bought a cheap USB-C hub/dock thing with a HDMI port on it so she'd have a single-cable solution for switching between the two laptops.
It turns out that the USB-C port on this laptop is a USB 3 port _only_. No alt modes, no special features, no DP, no nothing. Just data transfer.
But, I hear you asking, what about the dock she used with it for years that was with her old work laptop?
It was a DisplayLink dock so while it did have a USB-C plug on it, it was only using it for ultra-fast USB 3, not for alt modes, so it worked flawlessly.
Fricking hell Lenovo. How hard would it have been to stick a fricking mux chip in this fucking laptop?