Oh shit i havent talked about card game anime in forever uhhh -spins roulette wheel and it lands on gx- the reason why season 3 works so well isnt JUST the fact that the Protagonist fighting so hard is also what leads to things getting worse but also that it really forces judai to acknowledge that he really doesnt treat his friends like, well, his friends. All this time judai has been running around without a care for the consequences bc the duel academy was basically a sandbox for him to have fun without having to think about unfortunate things like "crippling depression" and "chronic lonely bitch-itis". We even see early on how this carelessness affects other characters, with manjoumes issues coming to light and sho's (temporarily) worsening relationship with his brother. so when it all slaps him in the face he isnt ready for it and it backfires into a dangerous downward spiral for him. its even made worse by the fact that johan (who he looks up to, so desperately almost) is there and adds even more pressure onto his decisions, made even WORSE when yubel possess' him. for all his talk about playing duel monsters for fun it was a way to for him to basically cope, and its why the duel with kaiba man early on and the final duel with yugi is so important, its basically telling him that its ok, its ok to have fun, its ok to mess up and lose, its ok to be vulnerable, your friends will be there for you, so you should be there for them too.