i think its a combination of these:
- OAIs models are much more token efficient. in some cases their new mythos-level model uses 1/4th of the tokens that mythos does.
- they reportedly have recently found another way to decrease compute needed "by half" in a breakthrough
- early on, they ensured they have much more compute ready, whereas Anthropic had to disable new users signing up because they ran out of compute
- OAI has fewer users (5mln codex users vs, what, 10mln claude code users?)