You might be unintentionally using the inferior 32-bit version… to ensure full compatibility with 64-bit Docker images:
Boot your Raspberry Pi 3 / 4 with the “arm_64bit=1” flag in its “config.txt”
Starting with the next update, our multi-arch Docker image is for 64-bit devices only
A 32-bit ARMv7 version based on the stable release will be offered separately. This saves weeks of build and wait time in the long run, so we can use those resources otherwise.
Docs are going to be updated soon: