WWDC has been nothing but disappointment for years.
Yes. They have introduced new coding guidelines to "improve" the convergence between macOS,tvOS,watchOS while breaking well established API to make things "easier".
They pushed autoi-layout, broke rotation API's which are still broken, replaced standard security and encryption frameworks with their own version to make them even more obscure.
They introduced "containers" which are still broken and document app development is a nightmare.
Resource management (nib/xib files) was easy. Now it is so bad that you create massive overhead on any SCM system.
And for the last kicker: Latest
Xcode is only available on Sierra with the latest Swift changes.
You people (not the quoted post) can claim I'm ignorant and hate Apple, but ...
Apple has change so much to dictate how to develop and is pushing in a direction that will cause more and more cookie cutter apps.
It is nearly impossible to implement all new features that a "complete" App should provide, but I understand that big developers with a service behind their Apps can still do that.
If you are a small developer, considering that hardly anyone is willing to pay for apps, only for in-app features, there is hardly any incentive to invest your time in Swift. It is as closed as it can be today and it will be even more so.
If Apple really would be interested, they would release a full toolchain (and I do NOT mean the Xcode GUI), to enable developers to run continuous integration on Linux, Amazon AWS or anywhere they would like.
But this is not happening. Apple up-sells you on Sierra compatible Macs with Gimmicks like the Touchbar, they refactor Swift to make it harder to integrate OpenSource API's and they desperately need you to be an all three platforms.
Look at Apple TV Apps, not happening.
Good watchOS Apps? Maybe a handful.
But the iPhone 8 will blow away all past profit margins.
Independent developers have no future on macOS,iOS,watchOS, although it was the best approach.
I give Apple all the technical credit they deserve, but I despise their politics and profit margins.