Absolutely, the man is an absolute clown. Not only has he lost the election, he's effectively lost the election after, because no opposition party is likely to reverse an 80 seat majority in one electorial cycle.
And I agree, whatever your politics, the demise of the Labour movement - or any credible opposition is not good for our politics.
Starmer should distance Labour from Momentum, if he has any sense. They are very damaging, in terms of appealing to the wider electorate.