As has often been said, that dock really is a computer.
I don't think that's a good thing though. No adapter/hub should be this complex IMO. I don't know how the ubiquity of USB got us to this point, it seems worse than before.
Because it's not USB it's Thunderbolt. Thunderbolt taps directly into the PCIe bus where USB doesn't. It only makes sense it is going to be much more than just a USB switch/hub. It's basically one of those PCIe expansion chasis that allowed extra expansion cards when your case only had 3 slots. Except, this is a nice neat little box on top of your desk.
Yeah, after buying a macbook pro I decided to buy an earlier generation of macbook air with some usable ports on it, there is no way I'm going to go around with an additional box. People complain MS is user-hostile but Apple does the same, just in their own way.