Game Freak 100% doesn't care about difficulty levels because they are so easy to implement but we still don't have them. When I play rom hacks I have started using a randomizer to edit base stats/ move power to use certain pokemon in certain ways; even though dragonite and gyarados will always be top tier picks because of dragon dance I switch their attack with their special attack because watching the anime as a kid and Lance's movesets in G/S and HG/SS make me picture them as special attackers. They both have incredible special coverage which makes the special sets fun and for even more fun I usually buff twister to 90 base power with the same flinch chance and change the move distribution and the level learned. The randomizer also allows you to change trainer pokemon really easily (just as intuitive and as fast as the showdown teambuilder). I bet anything it would take 2 employees a workday or less to hammer out an easy and hard mode which makes the lack of difficulty settings even more infuriating.Making video games more accessible is in and of itself an inherently good idea from a business point of view. If you can appeal to more audiences, that works even better for sales.
It seems to me that the prevailing concern here is not in regards to the idea of making the games more accessible, but rather the execution of it in practice. Yes, it seems the concern both in regards to newer Pokemon games and other franchises like with FE and Three Houses (well really, Awakening onwards) is that they focus on making the games more accessible to newcomers and casuals while not focusing on making the games more conducive to veteran players. Arguably, this is an execution problem, not one with the idea in and of itself. Older Fire Emblem games, for instance, had terrible accessibility to all but very hardcore Tactical RPG players and were difficult, until FE Awakening, Fates, 3H, and vice versa added a casual mode and other player friendly conveniences for newer players to get into the games more easily. That's not an inherently bad concept: what likely is the concern is how it's executed in practice making the games seemingly less fun for more experienced/hardcore players.
Arguably, older Pokemon games weren't actually difficult by any means. They were just more tedious and grind demanding because of poorly thought out level curves and lack of EXP All mechanic, combined with the shit/limited movepool options available to the player. The games from Gen 5 onwards aren't inherently less easy: in a vacuum the difficulty is actually pretty similar to old gens. It's just that the player now has more options at their disposal: infinite use TMs, everything has a better movepool, more ways to train and level your mons more quickly, Entralink Powers/O-Powers/Whatever, and vice versa. In other words, the player is more powerful. That's not necessarily a bad thing, since the AI in old gens wasn't that good and only made the older games seem more difficult because of bad game design, but they haven't powered up the AI accordingly to match the capable level of power players can reach in more recent games. A truly difficult Pokemon game would involve smart AI, strategic use of items, and well thought out movesets and teams. This is something you mainly see in multiplayer nowadays in the VGC and Battle Spot: given recent trends, it's clear they have focused more on that aspect of the games (Gen 6 frankly had some of the best multiplayer features ever) and back then mostly in the Battle Frontier or PWT. A simple way to include this would be to include difficulty modes that change how inherently difficult the game is, but I am unsure Game Freak cares about that unfortunately.
My frustration boiled over with the sword and shield base game which was the worst experience I have ever had with pokemon: first, the exploration aspect of pokemon has been dying since gen 6 and sword and shield didn't even have a single optional route (not to mention an aggressively mediocre wild area); second, I felt I could legitimately close my eyes and spam A and never be in danger of losing a single battle. It made for a crazy empty experience and I straight up loathe the base game because of it. Then I played a difficulty hack and I had a genuinely great time. The increase in difficulty really made the mobile pc shine and I actually had a reason to use a 10 pokemon roster beyond forcing myself to. The crazy thing is that Game Freak has it easy since the vast majority of fans judge pokemon by a different set of standards than other games ( don't have to worry about pesky things like pushing technological boundaries or an engaging story) but they still wont give us something as standard as difficulty settings. VGC has been a thing for a little more than a decade and they literally just put long overdue QOL updates in the most recent game to give some people easier access to competitive play which means they know there is an audience that would appreciate a hard mode, but they still wont do it. At this point I am just going to wait until a good rom hack comes out before I buy any of the games, its straight up embarrassing that they cant deliver on already lowered expectations.