The prediction was a 10x price reduction, so equivocating about "we don't know the size" doesn't save their prediction — a 10x price reduction would imply the model was likely more than 10x smaller in parameter count, and the price factored heavily in their prediction (they predicted its low cost would destroy other competition, since no one else could have such a capable model at that low price). And Haiku/Luna are nowhere near competitive with Astra or Fable, which doubly damns their prediction. I'm surprised you would pooh pooh the equivalence of K3 and original-Fable (which has been widely shown across many different benchmarks and even human preference data), while claiming an equivalence between Haiku and Fable!
If you stretch the definition of "previously-best 2026 model" a bit, Haiku 5.5 outperforms Opus 4.6 which was their best at some point in 2026 while being 10x cheaper.