But the way you frame it here, it sounds like listening is a passive activity. Don't the listeners need to participate as well ("active listening")?
You're right that we who enjoy talking about stuff like this need to adapt our communication modes to the sensibilities of those who don't. But we are still at a disadvantage that our message is inherently less interesting for the listeners than theater, Big Brother or whatever else it is that floats their boat. "Ideas or the lack of them can cause disease." - Kurt Vonnegut
In an ideal world yes! I think most party members would probably be more active listeners, but I have my doubt even about that. The thing is we want something from the people - we want them to vote for the Left! So we have to be interesting enough for them to be able to make the shift from passiv to active listening. So the responsibility is with those who want something.
I think often listening to the left there is a lot of metatalk - this is not a way to involve most people. Most people have a favorite topic that gets them interested and that is themselves. When they can see and feel and how voting for the Left will improve their lives the will listen and vote. And I am not talking about monetary promises only, but also quality of life in general.