

That’s because they’re the only ones that meet the project’s requirements at the moment, but that may soon change soon. Maybe you’ve seen the news that the project is in talks with an OEM for them to meet the requirements and have official support for GrapheneOS for some of the existing devices.
GrapheneOS isn’t dying. There’s an OEM partnership in the works and they’ll release devices with support for GrapheneOS in a year or two. GrapheneOS still provides updates and while the changes have made some things harder, the project is still going strong.