If you are an actual leftist (of any particular stripe) who reads theory and isn't just LARPing some fictional revolutionary vision in your head, then what you are against are 'unjustified' hierarchies.

Hierarchies that are created through trial and error of revolutionary attempts are justified hierarchies. Hierarchies based on whose daddy owned what business, are not justified. Hierarchies based on people being chosen by a group to centralize and coordinate activity, and having more privileges associated with their increased responsibilities is a justified hierarchy. Giving people more power arbitrarily, through no consultation with the community, and then allowing them to use that power to avoid responsibility, is an unjustified hierarchy.