OK, I finally got around to doing some A/B-ing of these boxes with the old CD issues using headphones. I checked Muhal Richard Abrams's "Blues Forever". It's a large band music allowing for a lot of dynamic variety. So yes, the new versions sound very treble-heavy and harsh. The large-ensemble passages are blurred and messy. The older versions sound significantly softer in comparison. For my ears, the old edition is much more enjoyable.
Checked the Dixon "Live in Italy 1" - same thing.