The point of a large deck (different school of thoughts for large decks) is to drag a game out and wear the opponent or their deck down. A lot of the cards would be considered filler to someone who wants certain monsters. The point of a large deck isn’t certain cards. It’s the ratio between types.
So yeah you don’t get your pretty little dragon card, but it doesn’t matter, that’s not the strategy.
This yugioh one in particular was about shuffling the deck, it had to be done properly or would be disqualified for not shuffling properly. So all he needed was one card that caused shuffle and it would take 30 minutes to properly shuffle. Lots of cards trigger shuffle, just need the ratio of types to stay alive till than.
If people didn’t surrender, they would probably win, but at what time cost.