Both musicals fall under the same stereotype. Cheap to run, iconic choreography and both can fall flat if cast with weak links. I've seen ACL numerous times and done the show 5x. Under the wrong direction, it can fall flat. If the director can't get the actors to properly tell each dancer's story, it comes off dated and boring.
On the other hand, I've seen Chicago on Broadway over a dozen times. When they keep recycling the same cast members, it comes off stale and dull. Chicago needs new faces in both lead tracks and in the ensemble to keep it fresh. As much as I adore Charlotte, I think her time with the show needs to end.
A Chorus Line revival played its final Broadway performance on August 17, 2008. The tour played its final performance on August 21, 2011. A new non-equity tour started in October 2012 played its final performance on March 23, 2013. Another non-equity tour launched on January 20, 2018. The tour ended its US run in Kansas City and then toured throughout Japan August & September 2018.