Use 'irrelevance' to stress that something doesn't affect a situation or outcome. Despite the outcry, the celebrity's opinion remained an irrelevance to the court's decision.
Pro Tip 2/3
Dismissive Tone
'Irrelevance' often implies disregard for the unimportant element. The teacher dismissed the student's tangent as an irrelevance during the lecture.
Pro Tip 3/3
Neutral Connotation
Sometimes 'irrelevance' is used neutrally, without criticizing the subject itself. The old law was an irrelevance in the modern digital age, so it was revoked.