Nothing he has done makes him sound like a plant.
Are you referring to the delisting from last week where people were doing stupid things, get delisted and then whinging about it? Liking twitter posts that say Starmer should be removed and calling him names or walking away from crucial votes? Yeah, that’s going to get you party support. They sound like idiots who shouldn’t really be politicians.
Making factless snide remarks about the party leader, who has had his background combed through, had people in his party read through his background and still vote for him? Sound like a Tory trying to make Labour in-fight so they are less of a challenge to the Conservatives.