UI that can be clearly seen and told apart from the content helps me as a user to "focus on the content" because I don't have to search for it and try and understand what is content and what is UI.

Stable consistent UI stays put and isn't constantly hiding and appearing and rearranging itself lets me develop muscle memory and a spacial sense of "where" everything is, so I can learn to get used to the app.
Instead of having to constantly relearn where everything is because it rearranges itself.

Clear UI, colors, stable unmoving persistent UI elements, which don't fade out or rearrange themselves, allow me to develop a familiarly with where things are.

I can quickly and easily see what is what without paying attention or even really looking at the app properly.

I can develop muscle memory of where I need to press and and where I can always find what I need.

I can develop mastery of using my device quickly, confidently and skilfully.

All of that is completely antithetical to the premise iOS 7 and iOS 26 are built upon.

UI elements constantly hiding themselves unless you use hiding gestures, hover states, and swipe to reveal means I can never rely on items to be where I expect.

I always have to look and check first.

UI "getting out of my way and letting me focus on the content" just means I can never tell what is UI and what is content unless I actually look closely at the app and pay attention.

"intelligently rearranging itself so what you need is always first" just means I never know what order anything will be in and always have to stop and check.

All of these "helpful" philosophies behind iOS's design decisions are just fundamentally wrong and bad for a consistent good user experience.

The colors used, the corner radius, the background transparency is all arguing about minor details when the fundamental principles the UI is designed from are just bad and fundamentally incorrect.

Some of iOS 26 looks pretty, some looks ridiculous, but watching the Apple design videos explaining why it was designed like it was just show the reasons it seems to randomly be good or bad, is because some of it is accidentally good.

The fundamental design principles underpinning the reasons for their design decisions are bad and mostly lead to pretty, well executed, bad UI designs.

The reason readability is terrible, there's no color, UI elements are basically impossible to see, is because that's the goal.

That's what they think "good design" is.

You can't see the UI? GREAT!
We are "getting out of the way of your content".
What do you mean you want to be able to see what you are doing? Don't be silly.

You can't see anything?
We are seamlessly blending the controls and OS together. It's MEANT to feel like one consistent blur. Why would you want to tell anything apart?

The more I watch the "Design" WWDC videos the more annoyed I get.

They are expertly implementing a goal which is itself a terrible goal.

They aren't bad at designing individual pieces, it's the larger goal.
They are brilliantly designing their goal. Their goal is itself just terrible. The target destination it itself a giant mistake.