Are bad and inconsistent design also core of the message? Because every single linked wallpaper page on that list has a different layout when they don't go directly to a wallpaper of unspecified size. Others have their sized versions listed directly inline and then we have the wallpapers hosted on an external server vs. hosted on gnu itself. It leaves a bad impression when they don't go the last 10% of the effort to present a clean site instead of an unorganized dump.

The message content is fine, even laudable. It's the tone that rubs a lot of people the wrong way.

I've been choosing gnu tools over non-free ones whenever I could for over ten years now, and I deeply believe in the GPL, but the condenscending attitude that a part of that community displays is annoying and counter-productive.