What do all of us with HDMI 1.3/4.. receivers. We have perfectly good amplifiers, but can't feed the requisite signals to the amps (or TVs in some cases). In some cases, the problems inherent in HDMI/HDCP won't even let 1.3x receivers to be able to switch a later version of the protocols; regardless of claims of backward compatibility. Buying an entire new receiver for the HDMI upgrade seems unproductive (unless you sell receivers, of course) a major waste of consumer dollars, and a whole bunch of electronics going to landfills for no real purpose.
What would make sense for the consumer, would be a "tuner" that can feed the audio amplifier portion of the existing receiver in your system. The tuner would have to accept HDMI 2.0+ inputs and switch them to HDMI outputs for the display and audio. The outputs would have to accommodate older versions of displays and provide a compatible format for the receiver decoding or pass audio into the preamp portions of the receiver. As I understand it (and this is always suspect, I am no way an expert) the audio formats will not generally change with HDMI 2.0. Simply the way you recognize them in the data stream to extract them and process them in the current manner.
If this is possible, it would seem we should encourage some manufacturers to create some of these "tuners" to solve the issues with the millions of older receivers whose audio processing is just fine and will be for many years. Now it is unlikely that major receiver manufacturers are going to go for this. It is not necessarily in their financial interest. Unless specialized competitors appear. The "tuners" would need to be economically priced. Once prices overlap with receivers; the "tuner" becomes pointless. A problem with many current devices that try to accomplish the goals on a limited basis with current protocols. I would think that $100 - $200 would be supportable. There is a huge potential market. As sources adopt the new standards, the receivers are going to take the brunt of the problems. And there are a very large number of people that will not spend the money for a whole new receiver.
Making this "tuner" even more acceptable would be allowing the remoter firmware upgrades necessary to keep them up-to-date. Something the major receiver makers already avoid for no reasonable technical reason. Remote firmware updates are a well developed and proven technology.
OK, why is this guy ranting about this. Well, I don't like how the industry is behaving. The primary reason though is to see if there are enough people around to make an effort to encourage someone to make this product. On this site, there are people who range from builders of these things down to people like me that just go out and spend scarce dollars to "keep up". There are certainly small companies out there with the expertise; and likely the resources to manufacture.
If anyone reading this feels like it is a good idea, please go try to educate/leverage the people that can do it.