Sword and Shield were bad because Nintendo were being accurate to how shit it is being in the UK right now. Absolute genius, I know
I fell off during Sun/Moon because the tutorial was way too long. I think I played about 10 hours before I got bored. The last one I played a lot of was X/Y. I respected that it threw you right into the game without any bullshit. The move towards a more story-oriented JRPG in Sun/Moon was interesting, but I think the story was too flimsy for me to get passed the fact that it essentially turned it into a slow pokemon game.
I really was enjoying Legends: Arceus, but it got pretty repetitive quickly, so when I put it down I never felt the urge to pick it back up. I feel like Game Freak has the ability to make something truly great with that direction if they really gave it a few years of dev time. Unfortunately I'm not holding my breath, because it seems as though they wanted to move on from Arceus really quickly in order to have people refocus on the mainline formula.
I'm still with the series because it's been such a part of my life, but I also don't hype up every generation like I used to. I've pretty much outgrown the mainline series. If they do something that catches my eye, I'll be rushing to put in my pre-order. At this point, it takes a lot more than putting out reskinned versions of the same game 2-3 times a year to pique my interest