The quotation that disagrees with Karlov’s defensiveness about chess is:
“He goes a little off-track, however, in his comparisons to other, supposedly lesser hobbies such as ‘mindless’ video games and ‘primitive’ traditional sports.”
This statement suggests that Karlov's comparisons undermine his position and reinforce a defensiveness about chess that may be unnecessary, as it implies that he feels a need to elevate chess by disparaging other activities.