No, it doesn't tell us what Keir Starmer would be like Grany. It tells us what a journalist*, who is as far to the right as you are to the left, wants people to believe Starmer is like.
So when do the far-left and the far-right agree? When they are attacking a coalition of the centre, centre-left and centre-right. Your argument, however, is not with centrists or, as I prefer to see them, the Coalition of Democrats.
Your argument is with the democracy of the Labour Party, where you, like every other member, will have had one vote. In your case, it did not go to the winning side, and you are unwilling to accept the democracy of that vote.
All this type of talk can do is destroy or split Labour. This is a split that is one I would be happy to see. In the same way, I would like to see such a split between the Neo-Liberals and the Conservatives in the current Conservative Party.
So do carry on doing the Democrats' work for them Granny. It will pay off nicely once we have PR.
*I am assuming this Peter Osbourne is the Peter Osbourne who was the former Chief Political Commentator of The Daily Telegraph. If he isn't, then it is probably worth making that clear.