Lol TR is done to death yes, but they aren't going anywhere...Can you blame them for wanting a pikacu that's sent them into numerous pokemon centers after 500-600 defeats?? All those times "feeling bad" and "blasting off?" NO way...besides, no matter how hard they get beat no matter how many times, they just keep coming back for more...They are clearly smitten by Pikachu's battling ability and think no other person besides the boss deserves it...But when something beats up on Pikachu like a rag doll, they want to catch it, but Ash and co go to stop them, then Pika gets them, and the cycle starts all over again....
But no matter how many times that they lose, they will always fight Ash's pokemon in arrogance, not always knowing that they'll lose...It's because they're arrogant, and too ignorant to see their lack of battling knowledge and skill. If not for TR Ash's pokemon would not be as strong as they are, have you ever considered that?? Ash won his very first battle, and it was against TR!!
To me, I see TR being more useful to the show's general welfare and Ash's strength as a Trainer that an 'unamed' cast member...I'll leave it at that for now....