I'm no fan of autotools. But I think I like meson even less. It
requires installing a whole new language (python); while this may be
acceptable for NetSBD's own build procedure, it significantly raises
the bar for cross-building pieces - if I have to not just copy over the
program's source but also install python? Honestly, I'd more likely
try to figure out enough from the meson description file(s) to build it
manually.
More generally, I don't really understand the recent proliferation of
autotools-replacement build systems. cmake, meson, ninja, etc, they
all appear to be trying to reinvent make and/or autotools as the tool
designer thinks they should have been, and they all appear to think
that installing a new, complex, and almost totally unsandboxable tool
as the first step to building the software you're trying to build is
completely acceptable.