...And tank their own profits? Cheap oil is good for literally everyone but the Saudis, that's the entire reason they've cut supplies since the glut of 2014-15.
US fracking is already barely at a fraction of capacity right now with how low prices are. It's not an essential industry for us, and our economy is doing fine without it. At this point the US can essentially produce unlimited oil at ~$50/barrel (break even for fracking with current tech [0]) whenever we want.
[0] https://www.reuters.com/article/us-usa-shale-kemp/u-s-shale-...
Everyone but the Saudis, and the Iranians, and the Russians, and the Venezuelans.
Like you yourself said, Saudis are obscenely rich. They can tolerate losses in profits. In contrast, fracking companies in the US can't, at least not without massive government subsidies.
isn't them running out of reserves a much bigger risk for them than them running out of customers?
No, not really. They still have the ability to flood the market and cause prices to tank, which would wreak havoc on the US fracking industry.