OpenAI has a lot of explaining to do here.
The “least worst” representation of the course of events is that their researchers are just jerks, and not behaving in a manner that’s considered acceptable in the research community.
Other alleged scenarios just go downhill from there.
It is worth actually reading OpenAI's response, which is basically that they were trying to see if their models could do what Anthropic had already done, and were surprised to discover that (a) Anthropic had not done it at all, and (b) in fact no one else had done it yet. And then they didn't want to give an Anthropic employee coauthor credit for work that OpenAI had done, which idk seems pretty fair?