So, I've always had this belief that wagering contests in casinos are not for regular or average gamblers, but they are only for high-rolling whales who have deep pockets and can easily rank at the top of the leaderboard, leaving no chance for average gamblers. That's why, it's useless for someone with a limited bankroll to try and compete in such competitions because they won't be winning anything but will only lose money in the process of trying to reach a certain wagering limit.
You are right, in order to win the wagering competitions, you need to have a lot of money in your bankroll. This means that even a 1x will give you a significant position on the leaderboard. The more money you have, the more advantageous you are.
The gamblers with less money will have to wager many times in order to even come close to the whales and when you wager more and play so many times, it increases your chances of losing too. So that's why we see a lot of gamblers do excessive gambling in order to meet the wagering competition and in return they just end up losing their seed money and nothing else is gained.