The first is that leaving the EU ends the obligation for the UK to partake in the free movement of capital. It’s not just free movement of labour that is guaranteed by the EU: so too is free movement of capital and there has always been a fundamental problem in linking to the two. Because capital can move vastly more quickly and easily than people (it has no family ties or school arrangements to worry about, for a start) having freedom for both capital and always meant that reward was going to shift from labour to capital because capital has the greater agility. The time has come then to make clear that it is restriction on the free movement of capital that will be needed if the return to labour is to improve in the UK.
We import capital in the UK. That capital adds to the productivity of labour and thus the wages of labour. It’s possible that stopping the free movement of capital will change the share of GDP going to labour and or capital. But it will be of a smaller GDP.
He’s going to make us poorer.