I'm feeling extremely uncomfortable looking at these kinds of regressions. There's probably some Boeing/NASA engineer pulling out his iPhone and making "simple" but potentially dangerous back-of-the-envelope calculations like this. We already solved the calculator many decades ago, then brought it into many portable devices, the first iPhone and now we see a broken version of it on iOS 11.
That is what really astonishes me about technology: Stuff can get worse. As you said, it is a solved problem, but unless someone somewhere is pushing hard, it will keep getting worse. People in charge make stupid decisions and the creators probably don't care because calculators are unsexy. Next thing we know, there is a billion dollar startup with a calculator app because the current ones are so shitty.
