The NetBSD/acorn26 port only supported ARMv2 and ARMv2a [1].

The earm architecture doesn't imply ARMv3, support for that has been removed from gcc which from memory was why the acorn26 port was deleted.

[1] https://wiki.netbsd.org/ports/acorn26/

Thanks, it seems I was confused by ARM3 (the implementation) and ARMv3 (the architecture, but not the one of the ARM3 implementation) once more. Yikes... this is quite a chaos.