Any of the first three Chicago albums were better.
Dynamo Hum was better.
Hotel California was better, at least "in it's style", as some say.
The Bollocks was better too.
So no, it wasn't the greatest album ever, not even close.
IMO Revolver and The White Album were the two best offerings from The Beatles, and Sergeant Pepper gets honorable mention maybe.
To tell the truth, any album that doesn't have Beethoven's ninth symphony or Handel's Messiah on it ain't gonna be the greatest album ever.
But that's JMHO. They axed, right?
Chicago V was their best. No filler, as on the double-albums, incredible playing by Terry Kath. "Dialogue", "Saturday in the Park", "A Hit By Varese".