Not at all.
Muslims believe in a long succession of prophets, including Adam, Noah, Moses, Solomon, etc. All of them were Muslims, since they submitted to Allah.
The last and greatest of these prophets (before Mohammed) was Jesus.
So if you accept this POV, all followers of God or Allah throughout history have been Muslims.
Forgot to add the Muslims do not believe Mo founded Islam. He merely reformed and purified it and gave it its final form.
I hasten to add I don’t believe any of this, but if you do the claim that Jesus is Muslim is a truism.
mohammad stole his many revelations and made up the rest
Islam wasnt around when Jesus walked on Earth..and the future mohammadans were worship the MOON “god” at the time
I could call a slice of cheese “ALLAH” if I were foolish enough to do so
mohammad’s allah.... not being the God Of Abraham... sort of rules out the whole Jesus as Mooselime scenario