Hell, I can't disagree with facts. There are button mashing kids barely having any idea and there are Smogon-hardened players that have been playing pokemon since the calendar year started with a 1.
However, I am convinced that the Mewtwo and Zeraora raids highlighted (together now with adventures), the most worrisome aspect, that probably gets lost in the
seasoned players vs kids playing argument: those are the extremes, but
the average player is terrible at the game (for endgame purposes and has no idea about strategy or synergies.
Now, I have unfortunately little to no evidence about the average playing age as surveying and sampling such an aspect would be hell-like - all online data surveys I could find are hugely unreliable for the trained eye, and I have spent far more hours reading stats in my life that I'd like to admit. As you correctly say, sometimes people just don't learn. The problem here is that SwSh structure opens the gates for
a lot of them to never have any incentive to.
You gave yourself the answer: easier interactions with the same mechanics should at least teach you how to be competent (whether this is achieved via: somewhat tutorial-ish battles, a stonewall preventing people from helping you with Level 100 Zacians until you've somewhat proven yourself competent, or something else, I don't know: your pick) and significant rewards should at least provide some sort of a challenge.
Instead, in most aspects, SwSh is a dumbed down version of USUM, or if you look from the other perspective, a glorified mobile game with some structure, but always aiming to give you the next dopamine release easily when you subconsciously know that a little button mashing will give you what you want.
Is the game reward structure that determines how proficient the player will be at the end of the game, not the other way around (the players' initial proficiency itself).
Again, I'm not advocating for a super-hard game and impossible rewards like
THIS (I actually did that quest blind with friends and was incredibly amazing: to this day, I still remember every step in the back of my head and how satisfying it was) I never would, but some semblance of reward structure, a modicum of a challenge, or some hard-wall to some rewards (like the MasterBall, a legendary encounter... again, your pick) would go a long way to prevent what I am disappointingly witnessing.
Is this the part where I mention again my 13 year old cousin getting stuck in Let's Go because he refused to catch any Pokemon and got blocked by a trainer with a level 24 Kadabra with his Pikachu still being level 15, asking me to pass him a level 100 so he could finish the game?
The same who couldn't figure why in Ultrasun his Lunala's 100 base power dream eater did no damage since he never actually read that it requires the target to be asleep?
And this is the part where I mention again my 13 old friend in 2003 who got to 59 wins in Ruby Battle Tower with no clue about RNG abuse for ivs (an incredible feat by itself, regardless of age) because he wanted a reward for his secret base (the Red Tent or a Statue, can't remember) so badly, I guess?
Such anecdotal evidence is pointless bar for reference. Dumb the game down and you'll progressively dumb players down, plain and simple.
A roulette addict would never play chess, but the same roulette player can grasp checkers' rules.