At least people can have this dialog now. Thirty years ago, if somebody suggested to a Chicagoan, or a sycophant of the CSO, that Orchestra Hall was an acoustical detriment to the orchestra, that person could get hung. As a young brass player, I had the CSO shoved down my throat constantly. I was an outcast for for not being one of their adoring worshipers - my colleagues would shake their heads. I always felt that with Herseth in charge, the trumpets and trombones constantly overplayed their dynamics, often times making little or no distinction between forte, fortissimo and triple forte. As a result, the horns often times had a hard, brittle sound because of their efforts to keep up. Arnold Jacob's wind capacity (lungs) had deteriorated by this point, so even he couldn't put a sufficient cushion under all that noise (no such problem with Pokorny). Because the brass were the kingpins, the percussion constantly played underneath them, except for sometimes overplayed timpani (really loud timpani in the Levine recordings). The woodwinds were nowhere as good as they had been under Reiner, Martinon or Kubelik. I really believe the hall played into this, as well as Solti's strange tonal concepts - what he was trying to get out of the orchestra (some say he was chasing after the Vienna Phil. sound).
I saw the CSO play Mahler 5 'on tour' in the latter 1980's - perhaps the single worst orchestral performance I've yet to hear. But what really shocked me, was just awful Dale Clevenger sounded. You won't hear ANYBODY say that! To me, he sounded as though he were using a mouthpiece that was too wide and too shallow, in order to obtain maximum agility and get all the right notes. His solos were were hard and 'brackish' sounding. I was astounded - he sounded nothing like he does on his wonderful recording of the Mozart horn concerti.
Well, that brings me to 2019 and Riccardo Muti. I've only sampled one of their recordings: Bruckner 9. It's OK. He certainly has addressed balances and brass timbres! The orchestra makes a lovely, dark sound. I just don't find him interpretively interesting in Austro/German music. I think the Giulini/CSO B9 is really very, very good (while the Solti B9 is a complete non-starter). To be fair, most of the CSO recordings with Giulini and Boulez are quite good. Levine is Levine (neither bad nor great in my book).