Who's winning?

i see a Pareto optimal frontier where they both are winners

cue Peter Gabriel

It depends.  Perhaps the person who spent $30K on speakers can replace them with $40K speakers with less inconvenience than the other guy can upgrade his soundbar.  

most people who spend 30K on anything don't do it for "satisfaction"

Depends on how you define "winning".

The 20k atmos guys might have blown the daylights out of the 500 dollar soundbar guys or the 30k speaker (60k, 80k whatever stereo) guys, it appears....Whenever i talk to those guys on the facebook groups, they seem very satisfied, might be the real winners...

p.s. they also seem to have rooms designed from scratch, spent more cash on the same (On the other hand, room construction is like  kryptonite for super audiophiles).