This is nonsense.
*Every* Dolby surround mix is back-compatible with ancient AVRs that only do Dolby Digital AC3. Even if your AVR doesn't decode Atmos, doesn't decode Dolby TrueHD, doesn't decode Dolby Digital+, Doesn't decode Dolby Digital EX --- there will, as has always been the case, still be a good old (lossy) DD 5.1 'core' embedded in there, and your 5.1 system will default to that, as long as there is a Dolby logo on your AVR.
(My AVR can do all of those, but I don't have an Atmos speaker setup, I ahve 5.2 (2 subs). All Atmos discs have a 7.1 bed mix. Some also add a dedicated 5.1 mix. If I play the 7.1 mix it folds down to 5.1. If I play the 5.1, well duh, it just plays it.)
So what exactly are you talking about? If your 'Atmos sounds like shit' and you have the most bare bones DD setup, then your complaint is about technology Dolby has been using for decades, not about Atmos.