This article shows that when Kimi3's chain of thought is prefilled to match Opus's, the rest of the chain of thoughts Kimi3 outputs very closely aligns with Opus's. That seems strong evidence that Kimi3 is partly a distillation of Opus. And Kimi3 is not a small model. No doubt a lot of hard work went into Kimi, but seems clear that distillation was used effectively as well.
(though maybe there's another interpretation of the thought alignment?)
Didn’t Kimi3 release a week before opus 5?