Precisely because Mabon's origin as a 1974 invention is so well documented and so openly acknowledged even by practitioners, a number of modern Pagans and especially Druids decline to use the name at all, preferring the plainer Autumn Equinox or, within Druidry specifically, Alban Elfed, a Welsh-flavoured term itself coined in the late eighteenth century by Iolo Morganwg as part of his own invented Druidic ceremonial, so that a practitioner avoiding the openly recent Mabon may nonetheless be using an alternative name with an almost equally recent and equally documented invented history.
The disagreement over naming reflects a broader and ongoing internal conversation in modern Paganism about how much weight an admittedly modern coinage should be allowed to carry, some practitioners treating a well used, meaningful modern name as entirely legitimate regardless of its recent origin, since all religious vocabulary was coined at some point, and others preferring to mark the equinox by a name that makes no claim, however loose, to ancient pedigree at all, a live difference of practice and preference rather than a settled convention across the modern Pagan movement.
Others avoid Mabon by reaching for an older English name instead of a Welsh-derived neologism: Harvest Home, a term genuinely attested in English rural tradition for centuries before 1974 to mark the completion of the grain harvest, offers practitioners a name with real historical depth in the British Isles, even though its original sense was tied to the grain harvest specifically rather than to the equinox as an astronomical event.