Why not? If she sues him in California where they have a residence, she gets half in community property.
The sticky question is “what is the community property.”
I have a friend who got divorced after 15 or so years in California. (Frankly, he wasn’t that great to live with, and she was still young enough for another try at happiness... in her late 40’s).
He had inherited a modest sum from his parents, and had been very careful to keep it separate from their joint funds and in his name. It was NOT considered community property. However, her share of the home they lived in was, and he had to pay her 50% of the assessed appreciation.
I could see how Bezos could have kept his business property interest separate. Certainly, he can afford the lawyers to help in his legal and financial planning.
It will be interesting to follow.