Third class citizens are those who live in a country without much rights, for examples workers in middle-east don’t have much rights compared to the ones who immigrate to lets say UK/US/Canada. “work visa” people in US have far more rights than “work visa” people in middle-east. Transferring visa (“kafeel” in Saudi Arabia) from one employer to another is one of the biggest PIA.
Worker in middle-east is unlikely to criticize Pakistan because he hasn’t seen what he can get. Though he is very likely to criticize lack of basic facilities like water, electricity etc. But then how many of those workers have luxury to spend time online.