An important part of the truth.
We used to have a party on the left that had a mass membership, and a democratic structure that allowed that membership a reasonable input into policy making and overall control of the shape of party policy. Its membership sold it out to a group of activists who wanted to prevent any input that wasn't thoroughly vetted to ensure it was acceptable to the editors of the tabloids.
The rest of the left was already a set of smaller groups closely moulded round a fairly specific ideology or leadership clique. It hasn't changed.
We now have no political party that actually allows ordinary working people to even air their concerns within the policy making structure, at least not openly. The question is whether there is sufficient desire to create or recreate a genuinely democratic party of the left, or whether nobody is willing to deal with any form of politics that might upset Daily Mail readers.
The first thing ALL of us have to accept is that to make anything happen in real politics requires either fanaticism, compromise or complete ruthless amorality. We've got plenty of the first and the last in British politics. Are there enough people on the left prepared to compromise their ideals enough to form a genuinely democratic alternative?