I have always thought the Move sounded really great so I haven’t noticed a difference. But Sonos does make improvements to their devices through frequent firmware/software updates, so it is possible the sound quality has improved since you purchased the Move.

One of my favourite Sonos speakers, has always sounded great to my ears. I love them when set as a stereo pair too.

I love my Move, often take it with me to the bottom of the garden/ in my workshop when I'm pottering around.

Same when cooking on the BBQ, worth every penny!.