Just because I named two decks, doesn’t mean that there are only two decks. There are actually four in the current meta: the afforementioned Sludgelock and Zoo Hunter, plus Snake Warlock and Zarimi Priest. I just started with the two that are both generally good (Snake Warlock isn’t) and easy to play (Zarimi Priest isn’t).
There might also be decks that haven’t been discovered yet which counter Warrior. Or there might not be. But the point is that it isn’t actually that hard.
If people would actually play the best decks, we’d currently have a situation where the ladder would be 30+% Zoo Hunter, a bunch of people running Aggro Paladin to counter — because Zoo Hunter literally has only one counter — and then the three counters to Aggro Paladin: Plague DK, Rainbow DK and Reno Shaman. Plague DK beats Rainbow, Reno Shaman beats Plague, and Rainbow has a very slight 53-47 edge over Shaman. It’d be a five deck four class meta, and everything else would be a meme.
And of course Reno Warrior would have almost zero popularity, because Zoo Hunter would be everywhere and drive its winrate into the dirt.
We are only in this position because a lot of people have an irrational attraction to Reno Warrior, a lot of people have an irrational attraction to decks that lose to Reno Warrior, and a lot of people have an irrational repulsion from decks that counter Reno Warrior. And if people just flocked en masse to the actual best deck in the format, Zoo Hunter, then it’d all go away in a matter of days, no balance patch necessary.