They might be idiots, but they’re not wrong. Lefty tech companies filter out conservatives (ignoring the censor/filter trap)
They’re liberal - http://www.dailymail.co.uk/news/article-2802573/almost-silicon-valley-s-political-donations-liberal-candidates-new-data-reveals.html
And they filter out stuff that they don’t like -
Hell, they even filter out ads for cutting tools.
http://www.thetruthaboutknives.com/2017/10/avoid-facebook-knife-sale-censors/