Both are becoming more unstable by the day, but Saudi Arabia (i.e., the royal family) has a lot of options, and some of them are even better than what it is used to. Israel's only option now is one state. But it's not even an option, rather a certainty.
Donald Trump: Israeli settlement construction in West Bank should 'keep going' (Haaretz)
from the article: Alleged Iran plot is ratcheting already tense ties with Saudi Arabia