Thank you very much for your answers.
I was actually considering newer A4A and A6A receivers but did not like their cheaper looking and smaller display (and - to certain extent - overall design too) compared to RX780... So, I stayed on RX780.
In order to keep full video (such as Dolby Vision, HDR10+) and audio capabilities (uncompressed HD formats) I had to connect media player directly to TV and use eARC in that way:
View attachment 1637994
Actually, it's working OK except Philips OLED936 is buggy in terms of switching the audio back to the TV speakers.
Yes, agree, but it also a matter of customer loyalty which may stay with manufacturer for a longer time if they see extended support and interesting FW upgrades.
BTW, Yamaha added eARC support to this receiver via FW upgrade.
Maybe you are right: as per bluray.com, the number of Dolby Vision Blu-ray disks is by almost 5 times higher than HDR10+. (And often if there is HDR10+ on certaion Blu-ray - there is also Dolby Vision present too).
And, BTW, I tried but could not see the difference between HDR10 and HDR10+ ))
So, maybe I shall consider forgetting about HDR10+ and just switch to "normal" connection scheme via AV receiver. Hope that passthrough via AV receiver cannot deteriorate the quality of picture even a bit.