> 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".

« This was then translated to desktop apps at the same time desktop screen real estate became a non-issue for everyone »

Exactly. I remember opening a Metro/TIFKAM app for the first time on my new Windows 8 connected to my new 27" QHD monitor, and then staring in bewilderment as it went fullscreen and 95 % of the screen was just monochrome with nothing on it at all.

Wtf were they thinking? That I would enjoy vanilla sauce on my roastbeef because they weren't serving strawberries yet?

Still puzzling to me how such a multi-billion $ company can fuck up so hard.

I feel like wide screens and ultra-wide screens are massively under-utilised in UX design and there’s a lot of untapped potential there.