For all the people with ARC issues. I recently resolved mine with an HDMI 2.1 Audio Extractor. A full HDMI 2.1 4K 120Hz VRR goes to the TV, and an audio only goes to my soundbar's HDMI-in. The audio support is pulled from the audio out port via HDMI-CEC. But HDMI-CEC signals don't go from the TV to the soundbar so I don't have volume support with the TV remote.
Before doing this I was using eARC as the soundbar is HDMI 2.0, not 2.1, I'd get audio dropouts every 20 minutes or so. And having things identified and working after power on wasn't a given. Now everything just happily works.
This is what I ended up getting, there are non-switch versions. I have a PC, PS5, and XSX and a single HDMI 2.1 on the TV.
https://www.amazon.com/dp/B0CDGZSB71/?tag=neogaf0e-20