Catching/Combo chaining minigame
Thing is that this comes at the cost of traditional wild battling and removes most of the skill of battling in favor of waggle gimmicks. And every modern game has a capture chaining mechanic of some sorts.
Again, a standard feature in just about every game.
There's a few games that don't, but this is pretty common too.
Red, Green, Mina rematches
Again, nearly every game has some kind of rematch against prominent trainers.
Master Trainers rematches
This is one of the few things I would say would count as "extra content", but it's really just a series of random trainers. Nothing much to it, no additional quests or story, no gameplay extras, etc., it's just a series of trainers.
Pokemon following you
Pokemon Riding
Trainer Customization
Partner Pokemon Customization
I wouldn't really consider this "content" because there's nothing to really engage with and complete, it's just an option. I would consider these features, not content.
Playing with Partner Pokemon
This has been a thing in every game since XY, and even then other games let you play with any Pokemon, not just your partner.
Go Park Play Yard herding game
It's a quick, cheap minigame that doesn't really add much to the game. And other games have done them before as well. Also this replaced the Safari Zone, which while it was irritating, it was at least something involved and different.
I would say that, in general, that's almost the same amount of content that we see in most modern Pokemon games. I don't think LGPE is any more content lacking or simplistic than your average Pokemon game. I think that's just the Pokemon Go stigma.
Not really, no. Other modern games have more than just what you citied above. Where are the involves side features like Contests and Secret Bases? Where are the Battle facilities like the Battle Frontier, PWT, or even a freaking Battle Tower? Where are the online modes like the PSS and Festival Plaza? Every other game for years has had
something along those lines to keep players engaged, but LGPE doesn't have that.
But beyond that there are even more fundamental things missing that make it feel like a step back from every game EXCEPT the original RBY. They stick to the same 151 Pokemon (+2 event Pokemon which don't really add much) pretending like the last 20 years of new Pokemon don't exist when almost every other game has at least twice that much. They don't add any new areas or expand existing areas to make the game feel remotely sizable. There's little to no QoL features from other games (where are the regional gadgets?) or online modes to allow you to play with friends in multiple ways. There's nothing to do but catch the same pitiful variety of Pokemon over and over and battle a handful of trainers. And they think that is supposed to keep you engaged? That this is worth the same amount as masterpieces on the Switch such as BotW, Mario Odyssey, or Smash Ultimate? The notion that the two are even in the same league is utterly laughable. That's like a local playground thinking they could charge the same amount to enter their park as Disneyland.