What a weird discussion to have. People just associate a succubus with "sex demon that looks like a girl" and incubus with "sex demon that looks like a guy".
Honestly, I'm not sure broader less degenerate audiences associate incubus with anything. The most popular use of the word at present is an american rock and roll band, and their utilization of the term seems deliberately obscure in relation to our use case here.
Sure, we can get into weird technical discussions based on traditional depictions from texts and imagery in the past, but language changes over time, and how valid specific terminology is ultimately decided by people utilizing language to validate or dismiss terminology in current year.
I think this is really the only valid conversation we can have about it with one key distinction; this isn't a space where validation or dismissal are sensible, that wasn't my intent- apologies if it came off that way. Words can always mean different things to different people at different times and in this case we have an additional problem in contention, since part of this whole mess is how a whole range of japanese words often applied to sexually aggressive women all wound up being translated as 'succubus' for years.
I think if we want to talk about it in detail we probably have to:
1. Talk about it in the broader terms of the mythologically common precept arrived at in parallel rather than trying to track down some sort of "Ur Succubus" and recognize that terms like succubus and incubus are labels of present convenience rather than specific identifiers.
2. Recognize that the level of academic rigor being applied is probably about two hermeneutic fathoms beyond whats really appropriate to this milieu- but I've been surpised in here before. Academics get horny too.