Totally an Apple racketeering.
Apple is blocking users from running apps (obscure workaround aside) unless the developer pays a yearly fee. How is that not racketeering?
To be clear, we’re not even talking about the App Store here. This is for WWW-distributed Mac apps of the regular kind.
To be fair, the developer subscription includes tools and documentation for Mac/iOS specific development that a price tag is fair for. But for the use case of cross-platform (e.g. Java) open-source development, not even a standard CA-rooted code signing certificate allows distribution without the security error. You have to pay Apple for one, or else your app is 2nd class and your users need workaround instructions.