Would you vote for Labour in a general election (whether Sir Keir or Andy led the party)?
I think a lot of people on Lemmy support the Greens but I very much doubt that the Greens could stop Farage becoming prime minister. Labour are probably the best-placed party to do that.
If I still lived in England I would only vote Labour if they really were the only choice to beat Reform in my constituency. But unless there’s a radical change in the Labour party’s politics it’s going to be nothing but kicking the can down the road.