What you are saying is both wrong and right.This is false Information. The PlayStation 5 does not support Dolby Atmos or any other Dolby feature because Sony did NOT bought licenses to use the features in the PlayStation 5.
Microsoft bought the license for Atmos. They literally upmix everything and output it as Dolby Atmos, even at the menu.
Sony didn't buy the license and they can't do that.
Playing a Blu-Ray with an Atmos stream will decode as Atmos if your receiver supports Atmos. It is simple as that.
If I played Roger Waters The Wall Blu-Ray in my PS4, my receiver decodes it as Dolby Atmos.
Sony is just passing on the bitstream.