I absolutely detest the inaccuracy of the word "phobia". What do you think of this as a replacement?

I don't like any word with "phobia" in this context as phobia means "fear" rather than hatred. Accusing someones dislike as being based on fear is not always valid. On they other hand what you propose is also pejorative in the opposite direction as it labels s as "abnormal" which may be vehemently argued against. For me "anti gay" is perhaps unscholarly but it "labels the tin" perfectly.