I have gulped and used ARC for Sonos amps and sound bars.  It works the majority of the time, can be a little dicey with ARC extenders.

One thing I have not done is used ARC from an AVR to a television. How many of you are doing that and not getting trouble calls?  😳😳😳

And following that question, would you only use it on an AVR less than maybe 3 years old? Or trust anything that says ARC on it?