Turmoil in the Middle East is nothing new but this does look a bit worrying. The Saudis were always thought of as having bottomless pockets but that doesn’t seem to be the case anymore. Oil prices are at recent highs but can’t really go up that much more as shale oil then becomes economically viable.
Whilst the cost of extracting the oil and pumping it into a supertanker is well below its selling price, the national budgets are based on a the expectation of a certain level of revenue and when this isn’t achieved the coffers have to be raided. This cannot go on indefinitely, then the family silver has to go ie ARAMCO gets sold. Eventually there is no more money left to buy off the population and they get restive.
Perhaps everyone will learn to live together peacefully, defence budgets can be cut and new income sources besides oil can be found. Iran can agreed to western demands and have sanctions removed, certain states can stop sponsoring terrorism. I wouldn’t put money on it though.