Basically, the entire community agrees that the downfall can be traced to the shift to 3D (and the death of Satoru Iwata) but I've noticed a pattern in the games since then.
>XY+ORAS
>SM
>USUM
Easy, Medium, Challenging
>LGPE
>SwSh
>PLA
Easy, Medium, Challenging
>inb4 HNNN WASN'T CHALLENGING LOL
Fuck off with your Max Revives faggot
Anyway, makes sense that they'd be doing this to hit three different markets:
>young kids
>older kids
>young adults