If the laws and regulations of the nation are such that the citizens can’t make money, then the government has no choice but to cut taxes and regulations until private business can flourish again. Otherwise it’s a never ending strangling of business, lower revenues, lower tax takes, and so on in a downward spiral.
I can’t think of any other way out of the problem except enhanced productivity and trade. The government can’t tax what the citizens don’t make. Post-brexit and at the total end of the empire, Britain needs to become something like Singapore or Dubai - a hyper-capitalist free-trade haven.
Of course this will only happen after 10+ years of failure, leading to an erosion of living standards and endless finger pointing and blame. You are already seeing the collapse of the NHS and the FTSE lacking any global relevance.