I wouldn't put that much drama into nulls, these are mostly academic discussions. In real world its much less drama in well maintained codebases, once you learn working with them you don't even actively think about it. In the meantime, basically all companies run on it, and will do so for next 50 years minimum, plus you have what... 17 million devs working with it?

Defensive programming is generally a good approach regardless of domain or language used, and if used well you don't have to worry about nulls in Java, at least not in your own code.