The problem with the term homophobia is that's a misnomer as term because literally it means "same fear" when translated from Greek. The word in common usage is the shorthand for bigotry against homosexual people. Since the common usage is generally how words are defined, have definitions added, or are totally redefined. Which means in common usage; homophobia, as a term for people who are bigoted against gay people, is technically correct. Which means that homophobia as a term regarding irrational fear of gay people is technically incorrect.
A clinical phobia is described as: An Intense, persistent, abnormal, and/or irrational fear, dislike, and/or aversion.
Since bigotry is, more often than not, described as an irrational intolerance(see: aversion, dislike) of a person, group, idea, opinion, or belief. So by that logic most bigotry can be synonymous with phobias. The thing with phobias is that they can be conquered with desensitization, therapy, hypnotherapy, or medication. Though I think medicating for a phobia is just a bunk excuse to sell more psychotropic drugs. The thing is that a willing individual can get past a phobia, which means there really isn't an excuse to cling to the phobia, it also means there is no excuse for a projection of bigotry towards a group one has a phobia of. Using any legitimate phobia as an excuse to be an asshole to people is unacceptable, plain and simple.
This swings back around to the term; homophobia, and the fact that the term, just by it's wording, is incorrect. More so it's common usage addresses intolerant and discriminatory behavior towards gay people, so as common usage goes, this term being used correctly. In which case a true phobia regarding homosexual people needs it's own clinical term separate from the common term, or better yet set of terms, used to describe the actual condition(s) related to such phobias.