Google Cardboard is still open source, but Google is done with the project.
— Read on arstechnica.com/gadgets/2021/03/googles-vr-dreams-are-dead-google-cardboard-is-no-longer-for-sale/

My friend Douglas and my son Ian both noted how Google has a tendency to drop things before they’re complete systems. Oh well. Sayonara, google cardboard.