A series of 20 or more losses in a row can happen literally from your very first bet because everything depends on luck. So, it's worth noting that the martingale strategy sometimes doesn't really work on short distances, and I agree with you that it's pointless on long distances.
I guess it depends on the game you're playing. If you're playing slots, then yes, a losing streak can be even longer, but there’s probably no point in applying the Martingale strategy to slots. And if you’re having a 20-loss streak in betting, then maybe it’s time to consider stopping those bets, because clearly, you’re not very good at that particular game. The Martingale strategy in gambling has been discussed countless times, but I’ve never seen a single player say it’s a good idea.
I often play slots and I am also one of those who believe that winning here is really just luck and I also agree that martingale will not work in slot games. because there are games that seem to follow the martingale method like dice games based on my experience here.
Then it is difficult to beat the casino or house edge, easy to say but difficult to do, sometimes for some gamblers when they feel lucky they feel like they can beat the casino but the truth is that they are just daydreaming.