There won't be any excuse... he won and that's it. Personally, I don't think he will. If he does, good for him he would win first major league, which would be next step for Pokemon Master. Only way he can win these types of leagues and even champion leagues is if title Pokemon Master or steps for being Pokemon master are tied with show's endurance. You do understand that show promotes games, as long as games are made, show will be made. So, show will end ( Ash becomes Pokemon Master) when Pokemon is done. I don't see Pokemon stopping anytime soon. Pokemon hit peak of popularity in these recent years same as it was like 20 years ago. If Pokemon games will be made in 50 years, Ash will be with us for 50 years, that's a fact. So he will become Pokemon Master in like 2070( if games end on that year), that's just an example. Even Rica said he has long way to become PM. So, unless steps for PM are huge and big, then I can see Ash winning leagues. But, I still think he will lose.
How is different? I am talking about structure of leagues. In Galar there will be 8 badges where participants must earn them in order to battle in tournament. In Alola; JJM , principal can battle.That alone puts it on higher pedestal than Alola league.
Alola could've handled better by making participants beating 4 kahunas in order to participate instead of saying everyone can enter. That's why many of us don't think highly of this league. This league is not same as other important leagues. 8 badges are still big requirement than have nothing. Hell even clearing 4 Kahunas would be better than nothing.