Her government proposed an unfunded budget that caused a gilt market panic. Part of the mortgage market dried up. Variable mortgage rates exploded. Pension funds had to resort to emergency measures. The Bank of England had to intervene.
For that matter aren't there Whitehall staff that could easily have said something?
It all seems bizarre from the outside.
And, of course, very Brexit.
"This is financially a bad idea" has been ignored since Brexit, and it bit hard.