> OpenAI said GPT-2 was too powerful to release

Because they thought such a text-generating machine will bring about a golden age of fake news. Seven years later I have relatives who send me every day some long-winded AI-generated bullshit. And I have seen with my own eyes how this sort of thing influences elections.

> Antropic said Mythos was too powerful to release. Both are GA now

Mythos was too powerful to release, hence it is not GA now. They released Fable, which is Mythos plus guardrails.