I've recently had the fortune of talking at length with my mom about her past, and one thing she brought up was how she felt when my dad brought that first desktop computer into the house. To her, it was kind of like a typewriter (which she understood), and kind of like a television (which she also understood). You type things, and they appear on the screen, but -- and this is the spooky bit -- other things may appear on the screen that you never typed. It's something she got used to quickly enough, but never totally came to grips with.
I think most people -- even very smart people -- are like that. They don't know how to deal with a machine that works semi-autonomously, in ways that don't obviously correspond with their input, nor to form an internal model of how it works, nor to engage with the machine transactionally in order to successfully operate it to complete a task ("if I do A, the machine's internal state will become B and I can expect its future behavior to look like C"). This comes natural to us, because we're techies and this is what we do. Some people can sit at a piano and play it like nothing. I can't!
The insight of the GUI was to draw a representation of the machine's internal state (or a highly simplified model of it) to the screen in terms that humans readily understand, along with available options for a human response (in the form of buttons and pull-down menus). Early GUIs prioritized the mapping of machine models to aspects of the real world, leading things like the spatial Finder which presented the file system in such a way that we can use our instincts for how we find things in real space to navigate it. This approach gets you some leverage, but there are limits to how far you can go with this. As time went on, we ran harder and harder against those limits. Typical office users may have fared okay, but then computers started to enter the home in a big way AND started to be networked in a big way, leading to a whole new base of inexperienced users -- who might've otherwise never touched a computer in their daily lives -- confronted with an overwhelming tidal wave of possibilities. And they became baffled, mystified, and frustrated by even the easier-to-use, Windows 9x era interfaces we had. And then, a decade later, smartphones created a whole new base of confused users. So the designers of today, having exhausted all the good ideas of how to solve the problem, resort to the UI equivalent of shouting at a deaf person: dumbing down the UI, removing elements considered to be too distracting, enlarging and spacing out the ones that remain, replacing specific error messages with meaningless but inoffensive blobs of text ("Something went wrong", "There was a problem", etc.).
Even more maddeningly, some of these changes were inspired by corporate communications. Some of these new error messages ("We're sorry, but...") resemble the old broadcast-TV error message of "We are experiencing technical difficulties. Please stand by." But the thing you have to understand is, this sort of communication works on normies. They don't need specific details of what went wrong, what they need is to be reassured that everything, in fact, will be okay. From an appealing-to-normies standpoint, "We are experiencing technical difficulties" would have been a vast improvement over a common Windows 9x error message -- "This program has performed an illegal operation and will be shut down." To a normie, "illegal" means criminal! The Feds put people in prison for a long time for computer crime; imagine the panic that would set in if you, knowing nothing about how a computer works, were suddenly told that it had done something illegal!
So really UI designers are just prioritizing soothing users over giving them actionable information and fine-grained control. The next revolution in UI design will be in making users well informed and capable without alarming them. I'd prefer that everybody toughen up a little, and basic understanding of how these machines work becomes a part of our civilization's literacy requirements, but that's nearly impossible to achieve given current market forces.
