If Ford thought those axles had safety issues I would think a recall would have been done during the production cycle.   As soon as the problems are mostly beyond the reach of the lawyers the customer is out of luck.   I fully agree with you that such an axle break is a hazard, and your trust with Ford is hurt big time.   If you end up out a couple thousand bucks on this one you will be annoyed, but if the thing broke and family ended up in the hospital with big problems and bills you might be thankful it wasn't any worse than this.   My wife took an involuntary cruise through a red light one night in Sioux Falls due to a ruptured brake hose on a 90's vintage Buick many years ago, the parts guys said those go out all the time - funny more people don't get hurt.   Junkyards might give you some perspective, if axles are scarce you can guess how big the problem might be.