The limitation is that by wanting a USB-C hub, you've painted a dollar sign on your head. USB-A hubs are cheap and plentiful, and for many applications work fine with C devices with an A->C cable. If that's not sufficient, you must be a big spender.
This doesn't seem accurate at all. There are cheap usb-c hubs which only pass down the usb3 capabilities. The expense comes down when you want to be driving 4k monitors, 1gbit ethernet, and charging your laptop through the same hub and cable which requires both extremely high speed data exchange combined with heavy duty power transfer and management.
The expense is not the problem, inability to look at hubs and cables and reliably understand which ones can actually drive 4k monitors, 1Gbit Ethernet and charge the laptop at the same time without issues is the problem.
Usb 2.0 and 3.0 still works exactly as it always did. If you only care about basic usb function, they all work. It only gets complex when you are trying to run a 4K video and 80w over the cable.
