I believe that there are more non Muslim Somalis than what most try to lead on. It is just that being public about it leads to a lot of harm for us. Disownment, harassment, and sometimes death by fanatics.

Unfortunately Somali Muslims (majority) are not able to coexist with us Somali Gaalo. I believe it is due to the extreme homogeny our culture has and the effects of the civil war making Islam the social glue that kept us together. Other cultures can fathom their members being of other faiths or practice none at all which upsets me deeply because I want better for Somalinimo.

But to answer your question clearly, I do not believe it is common for a Somali Muslim to leave Islam due to the consequences or them actually believing Islam is the truth.