Well, the US legal system is that broken, I see him with high chances of winning, somehow? (like "we give you 50% of what you are asking for but shut up now")
If you are confident that you can reach arbitrary judgments in about 1% of all cases, maybe via corruption, political influence or just random arbitrariness of court decisions, would this mean the expected value of this suit is approximately 1.3B usd minus ~10m legal fees?
Yes and in this case, it's not even that much an arbitrary judgement. I don't like the man but Musk has far more standing to go against Microsoft and OpenAI because the shenanigans they pulled were just that much more brazen.
IAAL (not legal advice) and find your comment confusing: first, because standing is a question of whether you can even have your complaint heard by a court; and second, because “brazenness” doesn’t necessarily make a case stronger.