No, not at all.
My own interest in dating the gospels late has nothing to do with arguing for a mythical Jesus. I am not interested in arguing for a mythical Jesus as I have said many times in the past. My interest is in explaining the literature and evidence for Christian origins using the same basic methods I learned as a student of ancient, medieval and modern history some years ago now, and as I still see in vogue in history books currently being published. They even apply the same fundamental rules of evidence and inquiry that I imagine crime detectives or court-room judges understand. Generally self-testimony means little unless you can back it up with supporting independent evidence. If the external supporting evidence all points to a late date for the gospels, then why knock it? (External evidence may not always mean an explicit identification or testimonial, and it can take a range of forms, including prevailing ideologies, debates, literary styles and language, etc.)
The results of my approaches to investigating the origins and nature of the gospels, and the evidence for dating the literature, lead me to believe that the best explanation for the narratives of the gospels is that they originated as creative theology. I don’t know when, but suspect from the time of the early second century.
But it would not make any difference if the gospels were all dated conclusively between 70 and 100, or even between 35 and 65. That would not change certain facts about the gospels themselves, such as their literary and theological borrowings from earlier Jewish (and non-Jewish) literature, and their genre when analyzed from the perspective of ideological messages and communications rather than externals such as style or topics and language used.
Such an early date would raise questions in other ways, such as how to explain their stress on persecution at such an early date. But the historicity of their narrative contents stands independent of when they are dated.
