Not at all.
It's just not the same as it was before. Wich is a good thing.
Games like YGO wich last for more than a decade MUST change in order to stay relevant, and interesting for that matter. The game, when looked objectively, is better than it ever was. It's more complex, more detailed and a lot more strategic than it ever was before.
Sure, these things came at a drastic change of pace and mechanics but the core is still the same, simply upgraded to stay fun and interesting.
Meta decks are indeed broken, but that's how they've always been. You think original was better? Cyber-Stein. Chaos. CardCrush.
You say you love GX? Monarchs, Gladiators, Lightsworns. 5D's? TeleDad and BW say hi.
The point is the competetive scene has pretty much stayed the same at its core. It simply scaled up along with the rest of the game as time went by.
I wouldn't say ruin, more like dead. But yeah it hasn't been good in a long time.
In no way is it dead, pal. It's going stronger than before.
Yeah GX was the last yugioh that was good. I just feel like there is no skill in deck building anymore when all your cards stop all card effects and you can stop summons. Its like you're playing alone.
What are you reffering to specifically?
Deckbuilding is still quite a challenge, that's if you wanna be original. People always net-decked and had cheap builds, ever since the original too.
You could argue that nowadays, its even harder to build a consistent deck as just 2-3 cards can screw up your strategy and cause a dead hand if you draw them at the wrong time.
Synergy and control have never been so important.