>>57569495You're soooorta right, or at least not horrifically wrong, until you get to content.
It's actually more like:
Platinum >= Emerald > HGSS > BW2 >>
DP>RS>>ORAS>>>USUM.
I don't know what you count for content but lots of contents can be a bit underwhelming in a sense. Pokestar studios is pretty disposable nothing content for example and PWT also feels pretty disposable and is inferior to most battle facilities gameplay wise let alone an entire battle frontier. Musicals have zero mechanical depth or progression as well so are the epitome of fake content. Join avenue somehow ends up feeling like the most significant piece of ongoing endgame content.
HGSS has two regions but it doesn't end up adding as much as it should. You have more towns, but each ends up less developed instead. It's cool to see a giant map but the longer I play the more I realize how little it has going on. A more complex safari zone and some crappy touch screen mini games at pokeathalon also don't remotely make up for the loss of secret bases, archaeology, and contests, which did feel a bit lesser mechanically in gen 4 to me for some reason but it was still a whole major gameplay format with its own stats and strategies to sink your teeth into.
USUM just had nothing going for it, every piece of content feels utterly disposable. Feels like the endgame is mostly just catching a bunch of legendaries for no reason. These postgame story episodes are just nothing, extra story content put at the end instead of major goals to work towards. The simplified battle tower in USUM doesn't help, neither does it's sorry excuse for a factory.
Special mention to ORAS, which does bring back secret bases and contests, despite simplifying the latter to an unnecessary degree. It does fill itself up with another pointless chunk of boring legendaryspam with the hoopa portals and does the bare minimum for a battle facility but it's still a step up from all the other garbage on the 3DS and Switch