So this USB-C DP Alt Mode cable only works with the USB 3.2 Type-C port on my GPD Win Max 2, with spare USB 2.0 lanes for downstream USB devices. To get anything more than that I'll have to buy an actual Thunderbolt dock, which costs at least $200 and often more.
But GPD Win Max 2 has no lack of USB ports on itself so I'll pass on the Thunderbolt dock... I'll just accept the fact that if I want to dock my laptop with one single cable, I can only ever plug in USB 2.0 devices... which is fine, because keyboards and mice are not even USB 2.0.
@PeterCxy Maybe the #SteamDeckDock is a good option, as it does USB 3.2 + DP Alternate Mode with MST & USB-C PD?
Pretty shure some more afforable #dongles offer that combo as well...
@PeterCxy maybe your monitor or the iGPU doesn't support negotiating anything beyond that?