Sadly, AVR manufacturers have not been trend-setters due to heavy dependence on what TV industry does. For example, entire PC industry has video sources and displays predominantly with Display Port, yet no single AVR has those ports. As such, that new market is not available to AVR vendors and millions of PC users would never think of buying an AVR as it is not convenient to integrate those machine into PC home systems. Virtually every monitor has both HDMI and DP ports, for user flexibility. It's a norm. TVs have not been providing this flexibility and, by extension, AVRs have not either.
Until we get first TVs and projectors with DisplayPort, alongside HDMI, no AVR is going to intruduce them, unless, as you said, someone dares to become trend-setter. In recent years, vast marketing attempts have been made to sell AV gear to gamers with consoles. These attempts have been made with HDMI connectivity in mind only. Yet, the biggest source on potential new income from gamers comes from PC world where DisplayPort rules. There are many more gamers on PCs than on consoles. No one has dared to penetrate this market. This needs to change if AVR vendors want wider market and bigger revenues.