People tend to use it to mean, "thing I don't like" far too often these days.

Slop has a long history as word used about art. Joeseph Cambell mentions it, people criticsed hollywood of it, publishers complained about it.

I remember those days using the term slop for lazy, uninspired, thowing anything that stuck on the wall, etc. AI is just a logical progression of the same term.

some of, to the flat out worst, in their respective series.

TOTK/BOTW

Look mate, not everything you don’t personally like is “slop”.

And your other cases are pokemon (who's been accused of sinking since the 3DS days) and Smash's online. Not even the game, its netcode (which if we're being real is bad for 99% of Nintendo games). We don't need to invent reasons to hate Nintendo, okay.

TotK may as well be DLC for BotW, and Windwaker would have been more similar to those titles were it not for the technical limitations of the Gamecube.

You haven't played ToTK at all. And what is this weird statement about WW supposed to prove about how the Switch games are the worst? Are you suggesting WW would have been the "worst" Zelda game if the GC had the power of a console that came 15 years later?

This isn't even getting into how you're going to need to show your work for how Zelda 2, Skyward Sword, some of the mobile entries, and that CD-i game are all better games than BotW or TotK.

You're really gonna look at all those 3DS attempts to reboot the same NES game and tell me that's not slop?

Yes. Things aren't "slop" just because they're not great. Otherwise most things in existence are slop. You haven't thought this through.

Pokémon is seeing the worst quality of the whole franchise on Switch

You don't know much about Pokemon games if you think the recent entries are the worst received generations.

apparently Pokémon Go was just to train military robots or some shit.

Pokemon Go is notably not a Switch game.

You're really gonna look at 3DS models in a Switch game and tell me that's not slop, my opinion is just wrong?

Yes. An uninformed opinion that misuses terms is a wrongly derived opinion.

Smash Ultimate's online play has 11, ELEVEN frames of input lag under ideal circumstances, the metagame has been busted since Steve, DLC characters are OP, patches were promised, then canceled, and support is over now. You're really gonna tell me that's acceptable, totally not slop, my opinion just sucks?

Yes, the opinion of someone who forgot about Brawl isn't worth much.

I hope you play Switch games forever, and I hope you love it.

This does not hit the way you think it does. Most people don't have such an irrational hatred for the Switch that they've convinced themselves of a lot of untruths to justify their weird hatred.

Slop implies bare bones, generic, repetitive design, and thrown together quick. Say what you want about Zelda, but it has never been any of those.

And have you played Splatoon 3/Raiders, Metroid Dread/Prime 4, Kirby Air Riders, Donkey Kong Bananza, Rhythm Heaven Groove, etc?

The use of superlatives also don't imply quality.

They're painfully mediocre. The gameplay is straight out of Assassin's Creed 2 with some Skyrim sprinkles for good measure. Run to the tower, reveal the map, do the quest, check the box, go to the next one, maybe stumble across a cave with some minor loot. Snooze.