How exactly is the existence of multiple viable strategies, even OTK ones, not good?
The more strategies people have access to and can utilise to have fun, the better. I have a really hard time thinking of a reason why more options for strategies is a problem in a Strategy Card Game.
I saw a pro on twitter put it like this: too many match ups felt like they were "I play a card. It's removed by a spell. And then I die from 30." And that's the entire game.
There is (a) too much spell-based removal, (b) too many ways to die from 30 in one turn, (c) not enough ways to interrupt dying from 30; or (d) not enough good aggro.
I think it's probably some combination of all of these.