Not so sure since Anthropic has 4 model families while OpenAI has 3 for GPT-5.6.
Claude Fable/Mythos vs GPT-5.6 Sol
Claude Opus vs GPT-5.6 Terra
Claude Sonnet vs GPT-5.6 Luna
Claude Haiku vs ?
Claude Fable/Mythos vs GPT-5.6 Sol
Claude Opus vs GPT-5.6 Terra
Claude Sonnet vs GPT-5.6 Luna
Claude Haiku vs ?
Fable/Mythos are much larger than Sol. They match to Astra which is supposedly at least 10T. Astra is already publicly confirmed as a new family.
Opus matches to Sol. Sonnet to Terra. Haiku to Luna.
Anthropic is able to compete at the frontier high-end by launching massively large expensive models. But their inability to compete on small models belies their efficiency aspirations across the stack.