I don't recall Starmer yet having that opportunity.
The hard left are hoping that he won't.
It's always been the same story. The truth is the hard left don't really want to be in power because the hard left are all about purity, taking the easy moral highground, and grandstanding. See Corbyn and his "how virtuous am I" routine.
He didn't want to be in power. He wanted to be in opposition where he could say what he wanted and would never be held to account, never have to deliver and never have the stress of firefighting truly shît situations.
Contrast this with the Tories whose sole purpose is to be in power, are absolutely ruthless at gaining it, and astonishingly succesful at doing so.
The conversation here mirrors this. All we here is "waaaah waaaah moral purity" and complaints that the Labour party that is likely to win is not the Labour party they want. But the Labour party they want is not the one the electorate are willing to vote for.