Good article.
As I've argued before, I agree with SDD that Brexit appears to be having some positive impact on workers in industries with a typically high proportion of migrant workers. However, it's not the migration that caused wages in these industries to be so low in the first place, but the lack of workers protections that governments could implement at any time, whether in or out of the EU.
For me, the heart of the problem lies in the fact that we pursue an economics which prioritises growth in GDP over social value, the benefits of which overwhelmingly go to the rich (60% of pre-crisis GDP growth went to richest 5% of population). Work of high social, but low economic value, is disregarded in favour of that which contributes more to GDP. An interesting analysis from NEF gave examples of this: Care workers generate £9.50 in social benefit for every £1 in wages earned. Waste recycling workers generate £12. In contrast, tax accountants destroy £45 in social value for every £1 earned, and investment bankers destroy £7.
Until we start to prioritise activities of social value, and therefore offer appropriate protections to both workers and the environment (and recognise unpaid care work), I fear the benefits of Brexit to low-income workers will be short-lived. In time, capital will find alternative means of exploitation to lower input costs (e.g. expected increased funding / policy priorities given to research on driverless lorries in the near future). The article alludes to part of the issue here too: the unchecked movement of capital, which allows production (read exploitation) to move to places of low-regulation / cheap labour and the returns then exported to shareholders back home. An analysis by Global Witness estimates that for every $1 given in aid, $24 flows the other wage through capital flight.
So overall, I think Brexit is a bit of a distraction here. In the long term, the neoliberal economics pursued by both the EU and the UK will lead to similar outcomes: i.e. exploit the poor and the environment, and increase the transfer of wealth to the rich.