People link to everything from the Pink News (lesbians should accept penis, incest is fine) through the Morning Star (unashamedly communist) to Breitbart on here. We're adults. We can check out the provenance of sites, work out their political leanings and take that into account. I'd rather know what political extremists were thinking than stick my fingers in my ears going "la la la la la, can't hear you."
Putting yourself inside an echo chamber is how the Democrats in the USA sat cheering Hillary on as she made her infamous "basket of deplorables" comment (yes, I know it wasn't intended to encompass all Trump voters, but that nuance was never going to come across in a sound bite), then were surprised when Trump won.
And when the mainstream press (I'm looking at you, BBC) deliberately tries to censor the news (it's taken them till 28th August to cover this at all, and then they've left out the word "rape" and basically re-printed Aimee Challenor's press statement, taking it utterly at face value), it fails in its duty to report the facts and dig out the story underneath interested party's own, partial, slanted accounts. That drives people into the arms of Breitbart.
You want people to return to the political centre ground? Don't try to do it by censoring Breitbart (which will only turn them into "free speech" martyrs). Do it by demanding the BBC and Guardian return to doing proper journalism.