Not to be *that* guy, but this is still a game aimed at kids.
It's fine if you can solo the game with your starter. It's kind of inevitable with how levels work.
There are many other problems that would be better to address instead of this. Someone mentioned how the games don't teach people about its intricacies well enough. That's a good point to start.
It's not so much that it's bad to be
able to solo the game with your starter, but more the fact that most players will probably intuit at some point that doing so is a more optimal way to play the game than building a balanced team is.
There's this weird contradiction in the earlier games where team-building is arguably the single most significant component of the experience, but the player is basically punished the more that he or she experiments with it. The more you're splitting the Exp around, and the more you're swapping in and out new team members to learn more about your options, the worse you're making the grind on yourself. The player is disincentivized from engaging more thoroughly with the material. It's the sort of thing that makes it extremely obvious in retrospect why they forced stuff like Exp All in later games (regardless of whatever gripes we may have with the specifics of its implementation).
Also I think the devs mostly don't go into detail regarding battle system intricacies for two reasons. One, they know that dedicated players will put in the effort to learn them regardless, and those players don't need help. Two, lots of game developers seem to fear that they might scare away players if they drop too big of an info dump on them, which arguably makes doing so a net negative for the game overall.
When I was getting into the competitive side of fighting games in my twenties, I found it perplexing that almost none of the games that I played went to any length to explain themselves. Whether it was execution or strategy, you're almost always left to your own devices to figure things out. Like maybe you'll get some basic combo exercises to test your execution and give you a basic idea of what's possible, but the logic or precise mechanics behind why things worked the way that they worked seemed to be purposefully obfuscated, left to players to reverse engineer on their own time. And for a really long time I just found it strange that I "had" to seek out external resources for technical stuff like frame data in order to close the gap with more experienced players, rather than having some kind of in-game resource to help even the field. Like, I wasn't asking for baby mode auto-combo options, just some explanations for how the game actually worked.
My opinion started to change a bit when I noticed that such resources largely didn't help anything even when they did happen to exist. Virtua Fighter 4 has
some of the very best in-game learning resources for any video game that I've ever played in my life, of any genre. More than twenty years later, it's still the gold standard for such resources for fighting games as far as I'm concerned. And... it largely didn't help. VF had--and continues to have--a rep for being very difficult to learn and technically demanding, and I think one of the reasons that that's the case is because it actually tried to communicate its depth to the player. VF is a 3-button game with no meter management and perhaps the most generous input buffer known to man; there are many respects in which I'd consider it to be easier to learn than its contemporaries. But it didn't shy away from showing its technical side and as a result got a rep for being technically obtuse. I've seen more or less the same thing happen in one or two other games in the genre where someone will decide to read and play the tutorial/reference section from start to finish before even trying to get their feet wet in the normal play modes and just get so overwhelmed from the jump that it drains any drive that they have to continue. And that's still putting aside the fact that any developer-made teaching resource still runs the risk of being made obsolete because there's always the chance that the players might eventually
push the game into being unrecognizable from its "intended" state because they learned how to exploit both intended and unintended mechanics to a far greater degree than the developers had ever anticipated.
Same sort of thing applies across different genres, too. I've seen people spooked from Puyo Puyo, an incredibly straightforward match-4 puzzler of all things, the moment that they were exposed to any sort of high-level techniques.
So, like, I'm fine with Pokemon just dropping some in-game generic/vague hints about how "different Pokemon of the same species seem to grow at different rates" or how "different natures seem to influence different stats" and leaving it to the player to investigate the specifics rather than spelling everything out. Do I think it'd hurt anything if they just appended some more detailed explainers about EVs and other battle mechanics to the in-game Adventure Guide at the same time as they unlock the Judge function for you? Nah, I think that'd be cool, actually. But it's also something that I don't think makes much of a difference in any case. The players most in need of that information are going to find it whether the game itself explains it to them or not.
As I've gotten older I've also come to enjoy the "discovery" aspect of game mechanics more than I used to anyway. Like when Tetris 99 dropped for Switch I actually had a lot of fun figuring out how badge acquisition works and how best to prioritize targets, rather than having everything explained to me from the jump. There's a certain satisfaction to be found in chipping away at the mystery yourself.
Yeah I guess this is kind of a ramble and barely applies to the original comment, but I already typed it all up, so w/e.