Can anyone explain why??
She and her chancellor announced a series of tax cuts at a time when inflation is running at 10%. Even worse, they sidestepped the usual processes on fiscal responsibility and declined to explain how the tax cuts would be funded. The bonds market then panicked as a result, with the Bank of England having to step in and bail the market out to prevent gilts from entering a death spiral, which would have bankrupted pens…
Especially, I think that the cancellation of the rise in corporation tax was very welcome and in fact economists now say that the rise to 25% will make the recession deeper and longer (unsurprisingly, frankly).
The issue was that the other cuts, especially abolishing 45p income tax rate but frankly also the decrease of the basic rate, were not discussed, not funded (which is what spooked the markets since we already borrowed and spent like crazy during Covid), and frankly everyone agrees that they were useless. Of course abolishing the 45p rate now was also extremely bad symbolically (though in fairness it only exists since 2010-2012).
I think the plan has shifted from "pro-growth, nevermind inflation" to "a good recession will solve inflation". And a 'good recession' along with higher interest rates, the incoming budget spending cuts, and maybe tax increases is also going to be quite painful for the people.