Absolutely nothing. He's not been amazing by any stretch, but his net approval rating is -46, beating Liz Truss at the height of her unpopularity by a mere 1 percentage point. Liz Truss crashed the economy and the entire country knew it, while Starmer has... U-turned on a few things. Generally been a bit milquetoast. Speaks with a nasal voice?

His unpopularity is deeper than Boris Johnson, who was swilling wine with his mates while the rest of us were enjoying the delights of yet another quiz on Zoom, who illegally prorogued parliament to deliberately impede the democratic operation of parliament, ever reached.
And the same will happen to Burnham, and in two years we'll be going into another general election with the least popular PM ever and the Labour party will again be tearing itself to shreds, and hand the country over to Reform or whatever even more nakedly racist self-consciously obnoxious bile has emerged out of the right wing.