Well, yes, it's a community endeavor. But if the
majority of the community want to keep it, they will have no problem doing so - most jobs and media would be in that language. OTOH if you find that everywhere you go, you have to use English because other people do it - well, those people are part of the community, too. If most Irish want to speak English in most contexts, why should they be forced not to for the benefit of the minority that wants to preserve the language? If the minority really feels so strongly about it, they can organize as a
separate insular community, so that their children don't have to interact with other languages etc.
This equation is different when the dominant language is spoken by the minority, but that minority can overpower the majority for historical reasons (e.g. historical concentration of economic or political power in their hands) - a good example of that would be Quebec. But the proper solution to that is to prevent or fix the concentration of power, not to force anyone to speak or not speak what they want.