I think there's no point in making their games looking any different than they do (because it's part of their brand, now) but the correct response to a question of why they don't make a "better" looking game is that they don't care. Or, maybe, it's a taste issue. Flailing your hands about how people totally did not appreciate you going through the trouble of making the graphics isometric or hiring underpaid artists is not the way to go. It's maybe "honest" but it's IMO at best a misunderstanding of and at worst a severe lack of respect for art direction and visual design.