Fidelity isn't a sane investor?
Crucial X.ai bought out X with a minority of stock. X.ai as in the thing spun out from X to do ai using X's data. Fidelity seems to value X.ai enough to be happy to have gotten more shares of it using the X shares.
I swear if OpenAI happened like 1 year prior to the twitter sale then everybody would have a different opinion about 44 Billion being the correct price for twitter.