In the early/mid 70's I sold stereo equipment for a local "salon" here.
I never, never cared for "quadraphonic" sound, but nevertheless I sold the stuff.
(I pushed good 2-channel systems more)
I knew back then it was just a quirk, a flash-in-the-pan-soon-to-be-gone idea.
I was right.
Even the best systems back then never really impressed me.
Add to that, most people didn't even know how to set up and adjust these complicated things.
I'm a 2-channel fusspot, and I won't ever change.