SwiftUI was doomed from the beginning. Not only Apple completely blew the implementation, it was actually DoA by a bunch of super bad decisions that ultimately make it incredibly hard to work with and manage, especially on bigger apps.
1. It uses the builder pattern for views (familiar to those who used Java) but for some reason they decided to make it so that the order of the modifiers in the builder matters. Each modifier doesn't actually modify the main view but it modifies what the modifier before it decided to return. This makes no sense as the modifiers should each be modifying the main view to make everything predictable and easy to debug. I'm convinced no one (not even senior devs with 5 years of SwiftUI experience) understands how the ordering of modifiers works. It's just swap them until it does what you want it to.
2. The view lifecycles and code execution path seem random and hidden behind layers of "magic," making it incredibly difficult for developers to trace and debug issues.
3. It is practically impossible to set breakpoints for rendering and view construction, it's impossible to really figure out when re-renders happen and what drives them. I'm convinced SwiftUI apps are incredibly slow not because the SwiftUI implementation itself is slow, it's because, even Apple's own apps probably do a bunch of unnecessary re-renders and one no one seems to have any idea. This is unfortunately another design issue that can't be solved by just making SwiftUI more efficient. It requires simplification and tooling to help developers not footgun themselves.
4. Lots of issues start appearing later on in the development cycle because, for simple apps, bad SwiftUI design decisions and footguns have unnoticeable effects, until the apps gets more complex and things start breaking. Fixing these issues sometimes requires rewriting whole features or spending hours debugging.
5. There seems to be almost no documentation on Liquid Glass. It's laughable that after more than 1 year, Apple has simply refused to document or provide good examples for Liquid Glass, except for maybe couple pages that resemble the brain dump of an engineer that has never passed a writing class in college?
6. Stuff seems to be rapidly changing and breaking from version to version. It took days to make my app look and work the same in iOS 27 as it did on iOS 26, even though iOS 27 is supposed to be a minor bug fix release. We don't even use anything non-standard and don't do any hacks. This defeats the whole purpose of a simple UI framework that can be easily adopted to different platforms (this never used to happen with UIKit).
7. View debugger still has no SwiftUI equivalent. It used to make things so much simpler in UIKit when you could just see the view bounds, pick views apart and understand what's actually happening. SwiftUI has no equivalent other than `.background(.red)`. Terrible.
I don't know how Apple can salvage this beyond just undoing some of these terrible design decisions and making it 1. super simple to work with, 2. stop relying on magic, making things more explicit, and 3. providing actual 1:1 UIKit feature parity.