Look at MSM’s coverage of actual progressives like Bernie Sanders or anti-war voices like Tulsi Gabbard versus establishment candidates like Beto or Buttigiege. CNN ‘townhalls’ are case in point — establishment candidates are fed softball questions while progressives are hit with ‘gotchas’. The media’s posture towards Sanders in 2016 (and now) is another example. Clinton was mostly untouched whereas the MSM churned out countless hit-pieces against Sanders.
Look at media coverage from any major conflict — from Iraq to Venezuela. The media ALWAYS takes the establishment line, amplifying the view of the DoD/State Department at every turn. The NYT was one of the biggest cheerleaders for Iraq War II. There’s hardly a hint of Leftist foreign policy in the MSM.
The ‘establishment’ is not just ‘The Government’; it’s the people who wield the actual power. I.e, the owners of capital. The goal of progressives is to reduce the influence of the few and restore democratic power to the many. The entire neoliberal project has been explicitly anti-democratic: from Mises to the Trilateral Commission and beyond. That’s what progressives are fighting against.