It is the opposite: he wants the variations to be different and interesting. There are no repetitive puzzles in The Witness or Braid. There are themes, but each puzzle is unique.
I think you're probably right that's what he thinks, he's just failed to convince me to think the same way.
Lots of sequences of puzzles in The Witness are just “the same thing, in gradually increasing space, with no new mechanics in between“.
> There are no repetitive puzzles in The Witness or Braid.
I'm sorry, I really like both games, but this is unbelievably false.