They’re not late to the IPO party, which was postponed by OpenAI, It may turn out that that was a mistake. OpenAI probably should’ve gone ahead, particularly in light of the pending court case.
Also Apple could have filed the litigation right before the IPO and after a IPO announcement. OpenAI doesn't get to decide when Apple sues them.
Isn’t that precisely what being late to the party means? You should have showed earlier?