This is where you almost just have to sigh with frustration, when you have artists whose material indicates they are so close to something, only to identify the wrong target (or fail to identify the other part of the target).
The Wall is an epic warning against authoritarian collectivism. Listen to Another Brick in the Wall Part II, the famous lines about "we don't need no education" and tell me it's not a more accurate indictment of the Left than anyone else. This really just shows the power of narratives. The narrative is that authoritarianism comes from the Right, hence if you're against that you have to identify as left/liberal. I think it's no more complicated than that for most of these musicians, actors, authors.