The bottom of the pile didn't emigrate.That's the FG reading of the situation.
The real reading is that FF mess up after spending too long in government; FG are then elected by default in the hope that they will improve matters; although they have never been trusted with a majority.
Once in government, FG then makes life so unpleasant for those at the bottom of the pile that a great many of them emigrate. As the government doesn't have to pay for their upkeep there is a little more money for those who remain. Still, many of those who remain are in pretty dire straits, and FG loses support.
Having used emigration & austerity to "solve" the crisis, Irish society is horrified with FG and turfs them out of government again.
In 2016, FF had not managed to recover from their major fúckup with the property bubble, and FG did, for the first time ever, return to government; but having lost one third of their seats in the Dáil. In other words, the electorate did not see FG as having solved the problems caused by FF (cheered on by FG and Lab) during the property bubble.
The bottom of the pile are those who left school early and have no skills.
It was educated people(both academic and vocational) who left.