This has certainly been a long time coming and to be honest I'm mixed on this, it was honestly disappointing how Ash was handed the win which felt like damage control, but on the other hand he actually won. The Pokemon Anime is a mess (still love it), even at its best it still does trip over itself with the most common flaw being forgetting basic typing (like how certain types can still hit types ineffective against them, even XY isn't saved from this), especially with its continuity and often disregard of its own rules. Even taking out game rules which don't apply it breaks the rules of the formula itself or uses heavy doses of plot armor in exchange for natural progression. This entire league gave Ash plot armor like a perfectly firm fresh diaper. Like how plot armor has worked against him in every league (I'm willing to give his Indigo league fail a pass simply because Ash was a rookie, didn't earn his wins properly and had a lot to learn before becoming champion, doesn't mean I excuse the execution, just the fact Ash was a beginner way in over his head) By Johto and onward though there was little excuse.
I even feel this will make any future anime series with Ash continuing as the protagonist worst considering the most common reason for him "losing" was that he would be unable to continue, him continuing to Galar would highlight his previous losses in a worse fashion simply because he would move on from Alola to Galar with an actual win.
Since the latter has been confirmed true that makes every loss from Johto-Kalos worse considering "marketing" and "Ash winning= the end" were reasons given, but if he can continue from Alola to Galar then his previous losses are now worse in perspective, especially when you factor in how much plot armor was used against Ashy Boy. Especially his loss on the Kalos league. Why is it only Alola he wins in this case? Was it because the rules didn't have the same styles or rulesets as other leagues? If so this was just planned to have Ash win, which is disappointing. Again happy Ash won, I just wish skill factored in and not given such restrictions just to give Ash plot armor against everyone not named Gladion.
Not only that the Alola League itself was so underwhelming and rushed, which is how I've felt about every league after Sinnoh honestly. Especially Ash vs Hau, I didn't think they could make a battle worse than the battle of Ash vs Elesa but Sun & Moon was like hold my Z crystal. Don't get me wrong I'm happy for Ash's league win, its about time they threw the poor guy a bone and the trending is certainly satisfying, but I feel this goes in the same category as Orange League and Battle Frontier, not that its irrelevant, but that this league didn't have the same standard rulesets other leagues (even Team Rocket were allowed here and were casted aside just as easily as normal) had, and Ash was given plot armor to win rather than skill of his own which is the complete opposite of other leagues, where the plot armor was used against him.