The sad thing is that Apple seemed more inviting to developers before they got high on the App Store cut.
Every boxed Mac OS X came with a second disc containing the SDK (Xcode has always been an unstable cow, tho). They used to publish tech notes that explained how the OS works, rather than WWDC videos with high-level overviews that feel more like advertisements.
Back then they've at least made attempts to use some open standards, and allowed 3rd parties to fill gaps in the OS, instead of acting like a Smaug of APIs.
Because they were coming out of being at the edge of bankruptcy and needed any help they could get becoming profitable again.
My graduation thesis was porting a visualisation framework from NeXTSTEP into Windows, Objective-C => C++, because my supervisor saw no future on keeping the NeXT hardware in our campus, if he only knew what would happen a few years later.
They said it in the Epic vs Apple litigation, something along the lines of "we create the entire App Store market", like the 3rd party developers aren't.
Every boxed Mac OS X came with a second disc containing the SDK (Xcode has always been an unstable cow, tho). They used to publish tech notes that explained how the OS works, rather than WWDC videos with high-level overviews that feel more like advertisements.
Back then they've at least made attempts to use some open standards, and allowed 3rd parties to fill gaps in the OS, instead of acting like a Smaug of APIs.