Hating proprietary OSes is fun and all, but the Unix world has serious problems and we should be embarrassed about the situation if we're trying to persuade people of the benefits of open source and free software. The problem? Everything in the Unix world is broken.
We don't complain about it much because we're used to it, but it's really a shambles. Daily life on Linux, let alone FreeBSD, is full of basic things like sound and X/Wayland not working. I'm sure we've all experienced this. You do a system upgrade and you can't start your desktop. Or you don't do a system upgrade and you can't start your desktop. Programs you install from the distro repository just segfault on start. Your package manager got confused and can't install anything nor fetch the repository; you have to search Google for the command to fix it. All the docs are 5 years out of date and worse than irrelevant. Installing a Unix OS almost never goes how the guide describes. You'll be on the recommended hardware, following step by step and get an error that isn't mentioned in the troubleshooting section. The Live CD's environment features a README file that refers you to commands that don't exist to get your WiFi working.
It might be better with one of those basically-open-source-Windows distros like Ubuntu, but outside of that, even "user-friendly" desktop distributions like Devuan have given me several of the above problems in one day of use.
Unix is a beautiful thing. The idea of a community-developed operating system where everyone can really own their computer is beautiful. But it's all broken, and that's not okay. Windows users don't need to understand their operating system to be able to use it more or less without problems. How can we ask them to switch to an operating system where they'll have to deal with this crap that makes even us turn to support forums?