Agreed. This sort of issue has been public knowledge about Twitter for a long time. This sounds to me like an excuse to delay or get out with plausible deniability.
It came out recently they have/had been misreporting (overly) user numbers, so this external pressure which they're now forced to deal arguably won't allow any hidden manipulation to stay hidden.
So it may be a question of just how dishonest Twitter has been, which could/should result in shareholders suing them as well.
Elon himself was ranting for months about Bots and "real ID" on Twitter, and he did not bother to include due diligence before manipulating the market with a bogus offer?
Public knowledge != authoritative, due-diligence-level public statement
But he did know it was a problem [1], so it's at least a bit shifty that now he pretends he suddenly says that it is a deal breaker. I suppose a court would have to decide if he has a right to back out or not without repercussions.
Sounds like the excuse Edward Snowden's detractors used that everything he revealed was already known so he wasn't helpful. But having actual proof instead of easily dismissed rumors or "conspiracy theories" is important.