welcome to the party
it's a matrix switch, it doesn't actually have a complete 2nd HDMI decoding/processing solution. It just passes through. You don't have to have another AVR, you could send that output directly to another HDMI display (e.g. have a multich setup in the living room and then also feed HDMI to a bedroom TV or something).
It's not really the same concept as the traditional "zones" and it's easiest not to think of it in that light, but rather just as an HDMI matrix switch built in (which is what it is).
I also think it sucks that they got rid of the SPDIF 2.0 PCM to other zones, but the problem is solved with a simple optical>analog converter as pointed out above.
I hear ya re the zone 4 hdmi: my point about requiring an AVR is if you wanted sound coming out of anything besides the tv speakers. I guess many tv's have analog outs so you could got that route.