Here's the breaking report from TechCrunch.

The HomePod was one of those rarer things I decided to adopt early, and I wrote a few first impressions when I switched to two HomePod mini after using the original HomePod for a couple of years. In summary: the HomePod mini sounded a little cheaper by comparison, but I stress "by comparison." The original's sound was so "good" – deliberately in quotation marks – as to sound almost alien, inspiring worry I'd disturb my adjacent neighbours with its pristine but unadjustable bass.

It didn't take me long to forget the relative cheapness. Now the Minis just sound good to me (without quotation marks, and with pluralization, since I bought a second Mini before long. And that's the main thing: no matter how good the original got, I think I've confirmed through this transition that stereo anything is better than mono everything, so to speak. At retail, stereo Minis cost 200 USD, and stereo originals cost 600 after Apple's first price cut).

The original was a heartfelt experiment, years in the making. I'm a little surprised it ended this way, but the ending helps confirm that my subjective perception of audio quality may not be so far from some allegedly objective ideal. As John Cleese once said of wine, "don't let anyone tell you what wine you should like."