Studio monitors are not necessarily extreme neutral. They could have directivity-based balance problems, very bad timing, dynamic problems, subsonic filters (increasig GD), small (not tall enough) radiating area to suit primarily above mixing console. Flagship models could have questionable subwoofer units and unnecessary directivity concepts. Priorities are in durability and low costs. Sound could be artificial and lame, which is finally killed by room EQ with horizontally flat target.
Could you consider that they could be right and quasi-objective "spinorama tells everything" people are not?