The Irish native English-speaker advantage was a self-serving myth, not fact.

Evidence

As for the language issue, it is easy to see that, as Miller points out, “Anglicized middle-class spokesmen were generally unwilling to admit the existence of linguistic barriers to full acceptance in American society.” And so the myth was born that would later be used to explain why the Irish “made it” more easily than other immigrant groups (a questionable assertion): that they were native English-speakers. — Noel Ignatiev, How the Irish Became White, 145

Categorization

• SEED: Angle: ‘how success myths are retrofitted’ — the claim that a group ‘made it easily because they spoke the language’ fictions read in reverse. Ties to the reader’s category-reclassification/comparison frame.