Why does no one know what prophet Mohamed looked like compared to Jesus there are hundreds of pictures
Iconography is generally prohibited in Islan, especially with the edict of Yazid, which reinforced the iconoclastic beliefs.
In the 7th venture christianity struggles through an iconoclastic period, but the use of icons were reaffirmed by the 7th ecumenical council. Icons, to Christian's reaffirm that God became matter. Islam has no such belief.