As someone who very reluctantly fits that description, yes but no. I don't love FreeBSD any less or want to use it any less than anytime in the last 20 years, nor do I like Linux any more than at any time in the last 20 years (less, if anything). But NixOS is the "killer app" that has me on Linux instead of FreeBSD. If either FreeBSD gets a really good NixOS-like setup, or Linux-based NixOS becomes unmaintained, I'm happily going back to FreeBSD again, it has always been excellent and stable to me.