As details appear about how officials on the right of the party worked against Corbyn and the left in the 2017 election, how they moved money to MP candidates to the right of the party instead of marginal seats, and actually hoped the party would lose, what hope is there that Starmer can reunite the party? This wasn't just an anti-Corbyn stance either they worked against Ed Miliband as well. You could say they condemned a whole generation to living with food banks and austerity.
Things you find stressful that other people don't notice.