You guys complaining have clearly never worked in software development... or software testing in particular. Or for a product manager or board that will crucify you if you push the wrong feature ... that delays others or leads to a bug for end users affecting reliability.. Safe to say... another areas project (Liquid Glass) in a segmented company culture like Apple that didn't want it leaked... probably weren't too concerned about prioritising a visual change over whatever else they're working on.
The silliest little changes can add a metric tonne of testing requirements and you can only fit so many hours of that into a week.
Most of those guys diverse people probably spend most of their time ensuring that current releases work reliably across the web / Mac / iPad / iPhone operating systems as they go through constant patches and changes just to make sure existing functions still work and meet performance standards they have set... and on new devices / chips coming down the pipeline.