The gridlock is real whether it happens inside or outside the party. This is partly why we're here in the first place! Starmer is out because he couldn't do coalition management inside the Labour party.
Starmer being an ideologue is a pretty funny take. I think most people would say he failed because he's a technocrat with no descernible principles or ideas.
Diversity over everything. Does not care about anything else. He is not a technocrat, to be a technocrat he would need to have evidence based policy, which he clearly did not. He is a pure, single minded, ideologue. Every event, every opportunity was just a conduit to express his single mindless slogan of diversity being our strength.