I've been thinking about this. Thinking of the person who originally bought the x3100 I'm using now back in 2014. Well, it said it was 4K. Of course, we know now that it isn't really, as it doesn't do HDCP - so it is pointless, really just 1080 passthrough.
And it made me think.
For people buying HDMI 2.1 AVRs today because they need/want it to support their gaming (latest Xbox or PS) then fair enough.
For people buying HDMI 2.1 AVRs "to future protect". Well, you know what I'm gonna say. Whatever new things there are with video in (say) 4 years time. HDR10+++ or Dolby Super Ultra Vision or whatever it will end up being... surely there's a strong likelihood that whatever it is the AVRs they are selling today will not support it?
I am one of those that do not really need HDMI 2.1 today, but I need a new AVR because my Yamaha RX-A3030 from 2013(about 9 years) have a couple of strange problems (in my setup) and it does not support HDR.
So why not just buy a used AVR with HDR? The second-hand market is expensive and vary limited where I live. A used Yamaha RX-A3030 is about 400 EUR today, a new X2700H is 900 EUR.
I was about to buy a new AVR for 2 years ago, but I heard about the HDMI 2.1 and it sounded like a bigger technical step so I decided to wait. Unfortunately, there was some trouble with HDMI 2.1 that seems to be resolved now.
The problem with X2700H might be that it only got 1 port with 8K HDMI 2.1 but even if this port would be taken by a console (like PS5) I don't see that 8K will be a video streaming standard anytime soon (5-10 years).
Generally, I don't have the cravings to use every new sound\picture technology that is released, at least not on the release day. In 2018 we switched from Plasma to OLED and after watching the HDR effect we wanted to get it working. The problem was that the Yamaha did not support it, so we had to connect source > TV > AVR. Usually this is the way to go when the receiver does not have the correct support but, in this case, it created other problems like picture and sound dropouts. I tried to fix it for a long time, but I gave finally up and connected source > AVR > TV without HDR. There are also still problems with the Nintendo Switch, either we have video dropouts, or we will just get stereo sound, as today we choose stereo.
Otherwise, we do not run any complicated system, it’s still just 5.1 sound just like 10 years ago. I really dislike that the AVR are so involved with the video now a days, if the AVR do not support some picture related future, tuff luck buy new or get a load of problems.