> Always showing vital elements like the scrollbar isn't a skeuomorphic choice, it's always a good idea, they only started hiding them because it looked 'cleaner' to some UI designer.

There’s a lot of modern design in not happy with, but this is not personally one of them. If I can’t autohide scrollbars I try to turn them permanently off instead of permanently on. For some reason I find them very distracting, and since I anyway use a scroll wheel or trackpad or keybindings, I don’t need it to scroll. (If it’s on autohide, I use it as a progress bar when actually scrolling.).

But there’s a lot of these weird things that seemingly everyone else accepts that just really throws off my focus. Blinking text cursor is another one, I just can’t get any work done until the blinking is off. If an app or OS can’t do that, I won’t use it.

> they only started hiding them because it looked 'cleaner' to some UI designer.

They started doing it on mobile in order to give more screen real estate to the content area. This was then translated to desktop apps at the same time desktop screen real estate became a non-issue for everyone (a 32" monitor at 1600x1200 used to be a luxury, now it's mundane). Now no one knows if there is anything "below the fold" without initiating a scroll action, which just encourages people to further only focus on the above the fold content.

Interestingly the response to that was sites adding horizontal "progress bars" across the top of the viewport to indicate how much you had read. And with application and website control of the styling and operation of these standard widgets, everyone is slightly different, which increases time to become familiar.

It's been a race to the bottom, in the name of (the subjective at best) "clean design".

Skeumorphism isn't necessary for consistency in user interfaces, but it generally ensures a level of consistency that is honestly hard in modern interface design.