No you didn't give no alternative explanation.
I surely did. And from the moment where there is another explication, the explication proposed is conjecture. Nothing else. An explication must be specific. Yours ( that I do not remember... and as you do not want to tell it again...) was not. Many objections could be opposed to it. From the moment where there is many objections non explainable... yes, it is conjecture.
You had a reaction that, coupled with the one you have now, makes me think you seem to be stuck within your own belief.
Contrary to you, I have no beliefs. I have facts. Grounded by sources.
And I do not use ambiguous ones to elaborate things which does not fit with other sources.
Everything is a conjecture when it doesn't fit your own narrative.
Especially when it is grounded by ambiguous sources not grounded by clear other ones.
What you call my "narrative" has changed many times in the 5 last years.So much that I consider having pretty none, except that the 9th c. one is historically false, and that the Quran is not the production of it.
All my historical affirmations here are grounded by clear sources : Importance of Iraqi Arabs.
Nasara as Persian Christians and not Judaeo-Christian
Influence of Syriac on the Quranic script and motifs in the Quran
Iraqi monasteries
Inexact dates of the starting "conquest".
Etc.