Incorrect. Its basically 16 SSC's on a single board. The Zeus is good to connecting display items which are in close proximity to each other --- like a matrix or megatree. Power injection is like 10' or less from the Zeus.
But the Hubs are part of a more distributed design which allows you to inject power ~ 100' to the SSC and then 10' from there. So if you were doing the rooflines of a house, the hub + SSC(s) is perfect and Zeus is not.
Also, the Hubs have built in pixelnet splitters on them (Zeus does not) and the active ss hub also has the ability to output a DMX universe (zeus cannot).
There are other differences, but the main thing is that the Zeus is best for the highly concentrated and closely co-located RGB display items and not so good for the others.