It can still happen when different display panel pixel colour arrangements don't match subpixel rendering settings in software, though that'll usually happen with non-monitor displays like TVs.
It was better on previous versions, I think Mojave was the last good one.
Then I upgraded my son's laptop to Ubuntu 22.04 RC, and I was greeted with the same fuzziness. I hope that's only due to Wayland, I haven't tried out the X desktop when docked.