Not going to agree on that one I'm afraid. I think Labour's Brexit policy was reactive and flawed, but I don't really see how they could have realistically gone in to the election backing Brexit with any expectation of keeping Remain seats. In fact, they haemorrhaged votes amongst both Leave and Remain voters as it was. I also believe there's some more fundamental demographic shifts at play in those seats (or at least, the most recent analysis I've seen suggests there is, but I might have missed something). Starmer comes away with some amount of egg on his face for that, too.
I hope in the long run, when Brexit is shown up to be the idiocy that it is, that Labour's lukewarm reaction to it is seen rather more favourably. The damage is done and unfortunately we're leaving, but at least the Conservatives have to own their mess; I'm not sure that pretending that it's really a great idea after all (especially as polling shows that voters are increasingly thinking it's a bad idea in even greater numbers) does anything more than just chucking away Labour's position in the future.