We build our ARM images to support the ARM64 architecture primarily (as indicated in our requirements and prerequisites), with ARMv7 support also available. We do not provide or support builds below ARMv7 (such as ARMv6) for Portainer.
As architectures evolve and the world moves more toward 64-bit as the default, there is less and less support for 32-bit architectures available. In the case of Portainer, some of the binaries we embed are no longer available for ARMv6 and below, preventing us from being able to provide a fully functioning Portainer environment on these older systems.