The map says "how people react when you try to speak their language" Irish is the native language of Ireland. No matter how many people try to say otherwise even with the petty "people claim to speak it"
The Irish language is also in the middle of big revival after the British had criminalised it for centuries and tried to kill it. The fact that it still survives is a testament to the people. It is still considered Irelands language, and I know only a handful of a people of a certain creed that would say otherwise or try to dispute it, and they wouldn't be considered Irish imho.