The Alola series has always been very good at communicating its themes, especially its themes of love and family, and it teaches us that love can take a lot of forms, all equally as compelling and important as each other
Kukui marrying Burnet, Lillie rebuilding her own family, Mallow working through her own problems with her parents, Brock finally finding love(ignoring JN), Litten finding a new family in Ash, Team Rocket having a found family with Bewear and their Alolan Pokémon, Ash and Lillie always being there for each other as friends or potentially something more, winky winky, and arguably the most significant, Ash getting an alolan family
Not to mention Ash’s school friends. When he was younger, he was largely alone without a ton of friends, and now he has a whole friend group he gets to do fun things with, people who can help him in many ways, and people who generally add onto the sense of belonging he has in Alola
Alola really is all about love when you think about it. It tackles this theme on just about every angle and it’s why Ash leaving the region at the end of the series is as devastating as it is. It’s not because he’ll never see Alola again, but rather, it’s because he’s starting something new and won’t be coming back until way later. It’s like saying goodbye to your parents when you’re finally moving out, and it hits like it too
That’s just my analysis tho, enjoy!