Noun
distinction without a difference (plural distinctions without a difference or distinctions without differences)
(set phrase) A linguistic or conceptual distinction which is of no practical importance or which has no effect on meaning; a perceived difference where there is no actual difference.
In the end, it's really a distinction without a difference. Source: Internet
Steyer might fancy himself a Bruce Wayne-style billionaire to Trump's Lex Luthor, but most voters will find it a distinction without a difference. Source: Internet