What about all the stuff they've done to keep it open:
- Per-install boot security policies
- Custom kernel boot (kmutil configure-boot)
- Raw-image boot mode
- XNU source releases
- Disabling SIP
- Disabling the Signed System Volume
- Third-party kernel extensions
- Developer ID distribution and notarisation
- Gatekeeper "Open Anyway" override
- Hypervisor.framework
- Virtualization.framework
- Rosetta for Linux VMs
- Nested virtualisation
- macOS guest provisioning
- DiskImageKit
- Custom Virtio devices
- Containerization framework
> What about all the stuff they've done to keep it open
I don't understand the purpose of your reply?
One of your examples is "Disabling SIP", but you're replying to a thread that has already been discussing this very topic, so it makes no sense to ask us "what about" that.
> - Third-party kernel extensions
Deprecated: https://developer.apple.com/support/kernel-extensions/
The issue is really the difficulty of using macOS as an expert user, and this has become significantly more difficult over the years. You mention "Developer ID distribution and notarisation", but both of those are actually restrictions that were added later to a previously open system. Notarization in particular has become a major pain for developers. Also "Gatekeeper Open Anyway override" has become significantly more difficult for users over the years.