As Irish politics returns to its boom-era totems of lower taxes and higher spending, the Taoiseach has recently commented  that emigrants had been slow to return as they were worried they would be "screwed" on their taxes.

With Irish taxes comparatively low and 100 emigrants likely to give 100 different reasons why they are abroad, we can add this to the endless list of silly assertions about those of us living abroad.

Discussions of emigration in Ireland remain mired in such unfounded assumptions, even before they become beset by emotion and stereotype. The statistics on migration collected by the Central Statistics Office challenge many myths and could inform a badly needed debate on emigration.

In particular, new statistics on emigrants' work, education and returns demand greater attention. Emigration from Ireland has often been associated with a lack of work, and unemployment has certainly been a factor.

But it is not so important for this generation: 48 per cent of emigrants in the year to April 2015 were in work when they left; just 14 per cent were unemployed.

The current generation of emigrants are not only often employed but also well educated – even more so than the “brain drain” generation of the 1980s. About 40,000 emigrants in the year to April had a degree; 53 per cent of emigrants are now graduates, up from 42 per cent in 2010.

The proportion of emigrants who were students before leaving has gone up from one in five in 2010 to one in three in 2014-15, meaning that, over the past three years, 20,000-30,000 young people a year are emigrating straight from university or school.

Emigrants remain overwhelmingly young, with about 45 per cent under 25 and almost all of the rest under 45. These are not people leaving because they cannot get a job or simply to “get experience”; these are people leaving because, Irish or not, they do not see the opportunities they want and have worked for.

Why do they feel that such opportunity does not exist in Ireland? Because despite being the youngest country in Europe postcrash Ireland is a seniority society. Nearly half the Civil Service is over 50, with just 4 per cent of civil servants under 30.

Young Irish working people are the most overqualified in Europe.

Hiring freezes and higher retirement ages may have been necessary to correct the irresponsible spending of the boom, but they also mean fewer opportunities for the young.

To the world, Ireland projects an image of youth, openness and vibrancy, but to its young people work, culture and society often look old, closed and ossified.

So will we come back? Recovery is the narrative of the day in Ireland, “Europe’s fastest-growing economy”. But for the two years up to April 2014 only about 12,000 Irish came home. In the year to April 2010 more than 21,000 returned: fewer emigrants are coming home now than during the worst of the recession.

Return migration is a complex phenomenon. Returnees in the 1990s were, like the more recent emigrants, noted for their high skill levels: the growth and expansion of the Celtic Tiger offered great opportunities for the Irish abroad.

That does not, however, mean there is a “natural” circuit of talented young Irish people getting experience abroad and then coming home.

Structural issues limiting youth opportunity in so many sectors could lead to persistent emigration, while structural seniority and rigidity could limit the desirability of moving home for those who went abroad to succeed.

Yet the narrative of recovery and return remains based on assumptions: newspapers run features on those coming home to a recovering Ireland, and the Taoiseach said in March that returns would outnumber emigrants next year – unlikely given this week’s statistics.

It is not a certainty that emigrants of the postcrash period will return home. The emotional pull is strong, but if the things that led many to leave do not change, many may not. Ireland needs a real debate about emigration, one grounded in facts, not assumptions.

Dr Christopher Kissane is a historian at the London School of Economics and Political Science