I do not understand this debate. The project should decide on which autotools version to use and everyone contributing should make sure everything can be generated and installed with roughly the following:
Well, not only that, autoconf and automake files themselves can set a minimum version.
For the problem case of "my version was old, but still executed, and produced a build system that wouldn't build", this has already been handled for a long long time.
But yeah, either autoreconf or explicit autogen.sh works.
> autoreconf -ivf
> ./configure
> make
> sudo make install