When Metagaming hurts the experience rather than helps it.

[KilroywasNOTHere]

this is why YU-GI-OH has become a meme to anyone who isn't a metagamer trying to flex. If I wanted to play a coin flip or rock paper scissors, I wouldn't be playing cards.

What other "Competitive" games have been so thoroughly ruined by metagaming they've essentially turned into a coin toss or rock paper scissors?

 

[LordsFire]

The MtG experience hasn't been completely ruined, but it's been massively degraded for everyone except for the elite powergamers.

Mostly by the online card market.

Back in the day, you bought some packs of cards, then built a deck with what you had or could trade for. Now, in almost any group that isn't entirely amateurs or people who've made a gentlemen's agreement to work within limitations, people just order exactly the cards that they want to make their deck the best possible online.

And given the deck lists of professional players and tournament champions are listed online...

 

[Battlegrinder]

What other "Competitive" games have been so thoroughly ruined by metagaming they've essentially turned into a coin toss or rock paper scissors?

I'm not sure you can have a deck building or army building game that doesn't have issues with competitive play shifting a great deal of emphasis on the composition of what players bring vs how they use it.

Having a choice of what you bring means a degree of asymmetry in the base game design (or an utterly meaningless choice), and where that asymmetry exists, people will seek to use it to thier advantage and tilt the playing field in thier favor. That's the price you pay for having control of what your have to work with in the first place.