Interesting you mention the UAE, given its clear and overt bias in favouring nationals over immigrants in the labour market there (Emiratisation). You are correct at least in pointing out that the problem lies with the UK government for its complicity in allowing the undercutting of locals.
I don't blame Virgin for acting in its own interests to try and suppress labour costs but suspect (and hope) that thanks to regulatory divergence from EASA their search for UK licenced foreigners will be largely fruitless.
15 years ago, US pilots were sleeping in crash pads and cars parked at the end of the runway. It has always been a mostly closed labour market there and now it's staring to bite. Look at the situation there today. Do you think such wages would exist if the whole world was eligible for E-3 visas?
Opening to the world will only serve to jeopardise any serious rise in T&C's in the UK and must be opposed vehemently.