Most users will leave the default settings if they don't have an active need to change them. Easily usable (and understandable) tools and interfaces prevent most needs from arising in the first place.
Concrete example: The root account on many Linux distros is disabled by default. I've never felt the need to enable it, because sudo does everything I need. Secure default, useful tools, unlockable system.
Historically we haven't had either of those things. Poor design and implementation led to bad choices by clueless users. The resulting mess is used as an excuse to restrict freedoms. The cure is arguably worse than the poison.