Netbsd is often a better fit for the older or more resource constrained machines.
E.g., this hardware has 16MB of RAM and 4MB of flash: https://github.com/freebsd/freebsd-wifi-build/blob/master/bu...
32MB RAM: https://github.com/freebsd/freebsd-wifi-build/blob/master/bu...
So no new zipit z2 port? I doudbt it...