he has a teeny tiny bit of fact on his side:
(generalisation alert) London and the SE are the most productive in terms of GDP certainly. Thats becuase it has more more-productive sectors (as defined by economists) such as fiannce and business services where as the north has more less productive sectors such as manufacturing.
BUT
You could question whether we should infact value the producutivity of finacial sectors differenty given the mess it has left us with in the last few years. This governemnt once talked about rebalancing the economy back to manufacturing but i wont hold my breath.
Also, it has not always been like this (e.g. 1870s textile industry manufacturing in manchester, ship building in NE c. 1900s) places rise and fall.
Also, The headline figure also masks huge inequalities within london and the SE.
In terms of subsidy, it is open to arguement who puts most in and gets most out. the North has a higher spend on benefits and welfare, but the south has higher spend on transport and infrastructure, arts, musuems etc.
It could be argued that with a london mayor and devolution in wales and scotland, there are very powerful voices speaking for anywhere but the north, midlands and sw. And that the economic potential of the North, for example, is supressed because of this lack of voice at a national level.
edit: so it nothing to do with working hard or not, see also ‘path dependance’ :-)