There was a provision that Musk would be on the hook for $1B if a third party (e.g. regulators) blew up the deal in a couple enumerated ways. No such option was available to Musk himself.
https://www.cnbc.com/amp/2022/05/13/elon-musk-cant-just-walk...
It is embedded on this link https://www.theverge.com/2022/7/8/23201004/twitter-to-sue-el...
https://www.sec.gov/Archives/edgar/data/1418091/000119312522...
“Pay $2B and out” was not a choice available to him.
anyone who actually think he was forced to pay 43bn when he could have paid 1bn. (even 2bn) are just not thinking correctly.
https://www.theverge.com/2022/7/8/23201004/twitter-to-sue-el...
Meanwhile, Musk was getting absolutely savaged in the Delaware chancery court and they were just in discovery. He was going to lose and that would be more embarrassing (somehow) than this outcome.
All because he went off half cocked and didn’t write bog standard contingencies into his offer.
He’s come off looking like an absolute simpleton in this and that’s the better outcome for him than if the court case had proceeded.