It would be useful to have the Raspberry Pi 4 image built as 64-bit instead of 32-bit to:

• improve reuse of aarch64 build artifacts / sstate
• provide a more available test platform for integration of vendor aarch64 binary packages (e.g. overlap with rcar3 for Alexa wake word engine, etc.)
• potentially improve performance

After discussing this with jsmoeller at ELCE, he agreed it would be worth investigating.