The problem was that many/most jobs didn't pay enough to make ends meet (hence Ukrainians taking up some of that slack).
And as we know so very well from Econ 101, adding low-earning foreigners boosts the average wage so much...Brilliant...
How about paying the natives more so that they don't have to leave, be replaced by tax-subsidized foreign scum, and create a bilingual mess. And the obligatory gangs, of course...
Memo to econ idiots:
There is no such thing as cheap migrant labor. You will pay through your ass one way or another ... It's just that they will not send you a bill...but pay you will...