At first, I was in the OS>AG>DP>XY, BW>SM camp. But then I watched Lumoise Trainer Zac’s video about Ash’s character progression throughout each series. And it made a lot of sense and was really well-thought out. So well-thought out that I actually don’t think this could’ve been the intention, but it’s a really nice way to look at it imo. If you want to watch the video it’s called “The Evolution of Ash Ketchum|Pokemon Journeys” But if not I’ll summarize it here (though I’d still recommend checking it out since he explains it way better than I could).
But basically, it went like this. In OS, Ash went from a noob who got either things handed to him or just lucky wins to a genuinely good trainer. He also talks about how the Orange Islands saga was what propelled him into becoming that way with the unorthodox gym challenges he had to do.
In AG, he was a great trainer, and started training with his Pokemon more, actively teaching them new moves for the first time. But because he was a great trainer and was even a mentor now, it got to his head a lot and he became very cocky and overestimated his own skill a lot of times. Even to the point of being kind of conceited and ignoring advice from May (thinking that since he was her teacher, she couldn’t teach him anything) and Brock (thinking he didn’t need his advice anymore). Throughout this series, he learned to become more humble as a result, realizing that no matter how good you get, there’s always someone better.
DP: Becomes more mature, and while an even greater trainer than before, doesn’t oversell himself and realizes that he can learn from not only those with the same or more experience than him, but also those with less experience. His character arc here wasn’t about becoming stronger, but an ideological challenge with the whole Paul rivalry. Not only did he learn from others who were weaker than him, but also from someone who he actively hated. Showing just how mature he had become. Also, I’d like to bring up the fact that at the end of DP, when Ash was asked if he was going to go on another journey and compete in another league, he was actually very unsure almost as if he was questioning if he wanted to keep up with his dream (thanks Tobias).
BW: Okay, here’s what really helped me be okay with counting BW in Ash’s character progression (even though the reset was still a stupid idea in general). But he talks about how we actually have no idea how much time has passed in between the end of DP and the beginning of BW. And that after having defeated his greatest rival, made it to the Semifinals for the first time and even took out legendaries, Ash might’ve wanted to take a long break. You know, like getting burnt out? Since he’s never taken an actual break before. Meaning that it’s entirely possible Ash really did just forget everything because it’s been so long. Like how we forget a lot of stuff we learned in school over summer break.
He also mentioned that it was supposed to be a vacation. Ash wasn’t even prepared to go on a journey unlike in every previous saga, but he got excited. Basically, he was just rusty. The scene in the final episode with him remembering all his past companions and reaffirming his dreams was what led to his persona in XY. He was more determined than ever.
XY: Again, he was back to being mature and competent. But not only that, this time, he wanted to win. He was on a mission. Still using everything that he learned from all the previous sagas, the trainer competence he learned in OS, the humbleness he learned in AG, the willingness to learn from others in DP, and the never losing sight of your goal in BW. All of these qualities worked together to make him dead set on winning and more often than not succeed.
But in this series, he learned to not focus so intensely on winning and also appreciate the more finer things in life. To “stop and smell the roses” and appreciate the world around him. Leading him to take another break just as he did after DP, and then go to school in SM where he does just that. During his break in between XY and SM, he probably took note to keep up on his Pokemon training every now and again, which would explain why he still had his competence.
SM: Still a competent trainer, but now more of a goof. Just like in BW, he went to Alola for a vacation and again he got excited. But instead of going on a journey and looking to enter in a regional championship or anything of the sort, he decided to go to school. A way for him to do just what he learned in XY, to just stop, take a breath, and appreciate the world at large. To learn about more than just being a Pokemon Master. Heck, he even had to cook and do laundry for himself for the first time lol.
So yeah, I count every Ash as the same character now. Despite the massive problems I have with BW and SM. Honestly, I feel like I didn’t do that video justice, but hopefully you guys get the gist of it. I also added in some of my own thoughts and stuff that I personally took away from the anime in general and the video though.