Hold up Bowie's albums to Sparks mid-70s Island run and No. 1 In Heaven and you'll see how dull they are, maybe.
I like 'em both. I just can't comprehend finding tracks like 'Sweet Thing/Candidate', 'Right', or 'Station to Station' dull, all vastly different sounds and paces, and all ploughed through within months of each other. Or tracks like 'Blackstar', 'Lazarus', and 'Dollar Days', mysterious jazzy concoctions on the eve of his death. Derivative, in some cases, I can see - 'Life on Mars', for example, is an unabashed tracing of 'My Way'. But dull? I'll never get it.
But then horses fuck ourses I suppose.