Just try a simple thought experiment: invert the genders or skin colours in the headlines and see how they sound.
"The Blackness Project will make you wince. Because black people can be really awful"
Does that not sound extremely racist to you?
"Why the mediocre woman's days may be numbered"
It's a statement of pure sexism. The article, in case you care, is about how much men suck. Try publishing the same article with men and women swapped around and see what your progressive Facebook friends think.
"The country is screwed, the electorate is evil, but here are nine reasons to be cheerful"
I don't think it is possible to make a more extreme statement than this. You can't go bigger than the entire country (short of going to the entire world I guess), and you can't go worse than "evil". So describing the entire voting population of an entire country as evil is pretty much the definition of extreme.
Note that thinking democracy is awful and ordinary people around you are evil has a historical correlation with murderous extremism. It's like the classical warning sign that someone may be about to do something really bad.
My post simply lists out Guardian headlines for all to see. It originally had something like +15 points and now it's sitting at zero, apparently it touched a nerve with some people who can't stand the idea that the Guardian and Breitbart might be comparable.
Here are some more headlines from their opinion writers, just to disabuse anyone of the notion that the Guardian is somehow not a bastion of radical extremism. They hate white people, they hate democracy, they hate men, they hate voters, they hate tea and Thomas the Tank Engine. They make money out of peddling hatred.
"The budget should be less macho - how about it boys"
"Why do women lie more than men? Because we're nicer"
"The Whiteness Project will make you wince. Because white people can be rather awful"
"Sexists are scared of Mad Max because it's a call to dismantle patriarchies"
"Are you too white, rich, able-bodied and straight to be a feminist"
"Tea is a national disgrace: Britain's favourite beverage is a boring relic of our colonial past."
"The tyrannical world of Thomas the Tank Engine. Kids love this little dipstick of an engine ... but what a chilling isle Sodor is."
"What if men had periods? It's a question worth posing"
"Democracy is a religion that has failed the poor"
"The country is screwed, the electorate is evil, but here are nine reasons to be cheerful"
"The week in patriarchy: take a moment to step away for survival"
"Did you weep watching Wonder Woman? You weren't alone"
"Remember when men and women could be friends? Republicans don't"
"Why the mediocre male's days may be numbered"
etc etc.