Historically, it's interesting to look at the StatsCan longitudinal study on immigration that came out last year, which showed that the immigrants who came in the 1950s, 1960s, and 1970s, who were from a broader range of educational background, did better in terms of integration. There were many more blue-collar workers who came at that time, and they got blue-collar jobs. For them it wasn't a drop in status; it wasn't depressing.
It has to be said as well that at that time blue-collar jobs were better paid and were unionized, as opposed to now.