You would be surprised with how common it is for the lay person to have problems on their computer. I like to start from there, and suggest a free as in freedom software solution. Then, once their issue has been solved, I will talk about the free software movement, explaning that these are the reasons that have motivated the authors of the software solution I promoted. Hopefully this leads on to a discussion about freedom in the digital world.
For programmers, WSL with Ubuntu is a good starting point for those who are scared of Linux.
That is definitely not a good starting point. WSL is much more complicated and prone to breakage than running a distro directly. It litteraly changes the whole system to make Windows run on top of a hypervisor. A better way to try out GNU/Linux is to boot up a live environment on a USB stick or use a VM. Plus, WSL is only command line, and I would think that showing a friendly desktop environment is the best way to blow the assumption of GNU/Linux being hard/only for nerds.
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