In a UK context, journalists are on there because politicians are on there... and politicians are on there because journalists are on there. It's politicians that need to pull the plug - if they left en masse the journalists would go where they went, even if they stayed on X too - but nobody has the balls to do it. (Aside from one politician who for all practical purposes seems to do absolutely nothing: https://www.bbc.co.uk/news/articles/clyrx1ee2r4o).