If a person wants to install non free software, she finds lots of ways on the
internet to do so.
I don't see any practicle difference if it is offered by debian instead of
somebody else.
The truth is: most people won't stop using every piece of proprietary
software even if they are educated about the issues that arise with it. Many
people value freedom and privacy, but not everybody values them the highest
of all things in their lives, and that's fine.
I can't see why the debian operating system (which is by default fully free)
should become less freedom friendly just by providing a way for those persons
to do as they wish.
The fsf is trying to dig a tunnel through solid rock and doesn't advance one
tiny inch. They have to realise that their method won't work in a hundred
years.