Closing this topic. Everything that has been said has been said.
As the updated blog post notes, supervised is not getting deprecated.
If you came to this thread because you saw an unsupported message in your supervisor tab. This is because your system does not match the requirements of supported installations as defined in ADR-0014. This doesn’t mean it stops working today or that you can’t use it, just that the development team will not spend time and energy to make it compatible with your system as both Home Assistant and your current operating system continue to evolve. Others might still work on compatibility and will either contribute this to Home Assistant or share instructions as a Community Guide.