What HT processor HDMI 2.1, and does that matter?

I'm currently using a Marantz AV7702 and when I got a PS5, which I use to stream netflix, amazon, etc., and I'll also get some 4k discs for a select few movies I really love, I had that issue with the video cutting out you may have heard about. I had to use the HDMI cable the PS5 came with, which is HDMI 2.1 certified, and the problem went away, even though neither the Marantz nor my TV has HDMI 2.1 inputs. I've been lusting after an Anthem AVM60 for a while b/c I think that will be better HT sound than the Marantz, but it also doesn't have HDMI 2.1, and neither does the current AVM70 as far as I know. Does this matter? Are there processors out there that sound good that do have HDMI 2.1? Alternatively, I was thinking of getting a TV that does have HDMI 2.1, putting the sources directly into it, and using the ARC (audio return channel) into the HT processor, but I wonder, does that significantly reduce the sound quality? I am skeptical of a TV's ARC in terms of audio but I have no experience with it. Has anyone experimented with setting it up that way and how does it sound? Thanks.