I'm not in the majority here, but I don't find the game anymore or less difficult than original Red and Blue. To me the layers of complexity in Pokemon was always in link battles.

The single player aspect of the game was a fun ride, but just a means to level up your perfect IV Pokemon to 100.

What would the hardest part be in the original Pokemon for the US? (Red and Blue). Gym teleport puzzles? Finding legendaries? (Which even at that time you could get their location online)

I can't really think of anything super difficult in the original. Get your Pokemon to smash a rock in your way, learn surf to travel farther, obtain a Silph scope to be able to fight Ghost Pokemon.

And, at the time they had guides posted online or in book form. Today they are able to have much of those guides built in. All that said, I never needed any guides in the original other than for the following

1) To find the location of the legendary birds and Mewtwo 2) To understand IV stats better

I am as found of the originals as the next Pokemon fan, but I think we are letting our fandom get in the way of the truth. The originals were not hard.

If you mentioned Pokemon Yellow then I would tend to agree that it was a bit harder than the originals. Pikachu was a shitty starter. But still far from a difficult game to beat.

Your rival in the game was always a pushover l, the elite four we're super easy, and Mewtwo, once obtained, could destory anything in your path.

The "kids" game argument is weak, I agree. But Pokemon story was never hard. The complexities of Pokemon comes from the "end game" which is link battles or today just known as PVP.