When it's not done right. Some games have gotten it right, Dust: An Elysium tial, The Messenger, Ori and strider remake as the few examples that have decent 2D combat. The problem is 2d games have to directions and it becomes the most basic gameplay experience. There's no strategy you can learn to implement or at least it's as shallow as it can possibly be. 

I'm currently playing some 2d games trying to get some to gel, Salt and Santury, Ender Lillies, Tails of Iron, Streets of rage 4, Eiden Chronicle Rising and Hollow knight. They're all so basic, you swing the sword light or heavy, it's one click. Ender lillies has skills but again, it's so basic. 5 games in a row, all just boring one click button to hit an enemy. Salt & Sanctury has parry mechanics but it's unsatisfying. It all boils down to one button presses at the end of the day. 

What am I missing here, I know I used to love sidscrolling beat em us but in this new era of gaming it all feels peeled back. No skill or strategy besides moving. Salt & Santury tries to be souls but it fails, you're mainly dying because you get stuck between the boss and a wall. Devs can't implement unique movesets or mechanics. That's not fun.

Metroid Dread disagree.

The first time I actually felt I was in a real swordfight was Zelda2 Adventure of Link. I loved it, but ok that's a long time ago.

I still love 2D action games. Because there is no camera to worry about, I would argue action can be more frentic and precise at the same time.

Smups, Beat-em-ups, Metroid vania's, Run and Gun's, there is a long list of fantastic action games including recent ones like Cuphead or Metroid Dread.

One of the worst takes ive seen in this site by far.

Ori also have some great boss fights, as a result of the unique abilities. I quite like 2D fighting. I still think Raven Beak is one of the best boss fights in the history of gaming. Better get your skills ready, he is no joke.

That's one hell of a hot take, OP, even for you.

“Metroidvania” games aren’t my thing, either. On paper they are, because they’re basically the next step up from traditional Castlevania, Shovel Knight, Zelda 2, and Ducktales. But, IMO, none of the Metroidvania-types will ever be Faxanadu! :D

That said, Faxanadu would be shit for modern players. No one outside of my generation should play it.

IMO, beat em ups and hack n slash are more satisfying than Metroidvania-types, especially with multiplayer (local). And I also much prefer traditional Castlevania and the other aforementioned games.

But, if you want to enjoy a certain type of game, perhaps you have to be in the right mood for it. If you’re a depressive person, try RPGs and adventure games… I find in my emptiest times, they’re the best ones. Angry mood… hack n slash and beat em up :D

Anger and emptiness… what are some other moods…

Oh yeah! Extreme cheeriness! Every game is fun on those days.

Should checkout Jazz Jackrabbit 2 from Epic Games

Yeah, Ori is one other example where it's done right, It feel uniquely good and Dead cells gets it down cause it's not so basic. Just seems every 2d game I pull out now is weak and feels really basic. Perhaps my opinion is 2d sidescrolling can feel really weak and basic if not done correctly. 

Damn. I have the most milktoast of takes usually. I've had 5 in a row duds, games that are supposed to be great like Hollow Knight and salt and sanctury but feel as basic as minesweeper in gameplay.