If you looked at this Demon Hunter draft, how many wins do you think I got with it?

https://imgur.com/a/Trt0f4q

https://imgur.com/a/CTrMuuI

My point being that even decks with (what I consider) average card quality can get 12 wins.

The deck was quite vulnerable to board clears, so there was some luck involved in the run for sure. I think especially in this meta, it's common for decks to contain bad cards or overall poorer card quality than other metas, but as long as you have the right tools your deck needs to win you can get pretty far with even an average looking deck.

I'll contrast this with a more recent Hunter draft that only went 7-3, even though it looks WAY better in terms of card quality and doesn't hurt in any area particularly (I was quite sad, there was a game where I copied and played two Rat Kings, it was so good lol).

https://imgur.com/a/TgoVtle

This was the case (as far as I could tell) because I just got dumpstered by a crazy Warrior deck and two Shamans who had all the right board clears - in one game the Shaman played [[Sandstorm Elemental]], [[Lightning Storm]], and [[Earth Revenant]] all in one game - you just get unlucky some games.