You call austerity "ruinous", but what else do you expect them to do when the damage was already done from ~2001 to 2008? As you mentioned, taxes were already high and borrowing is not only expensive but also puts fuel on the fire, resulting in future crises.
Of course, "austerity" never really happened since the government's deficit was still over 3% of GDP when Cameron left office.
You call austerity "ruinous", but what else do you expect them to do when the damage was already done from ~2001 to 2008? As you mentioned, taxes were already high and borrowing is not only expensive but also puts fuel on the fire, resulting in future crises.
Of course, "austerity" never really happened since the government's deficit was still over 3% of GDP when Cameron left office.