"Why are so many exmuslims rightwing?"
Not in my experience. In fact in real life I haven't met one Ex-Muslim I know who is right wing. Most of those I know are left wing in fact. Others just middle of the road.
Maybe you haven't really delved into politics with them?
Secondly many right wingers say they're centrists around lefties.
I'm not naming names Hassan, but you recently posted a picture with an exmuzz who I know is right wing who I've heard say he is "capitalist" in person.
I forgot to say in my first post that I've met some exmuzz who have gone as far right wing as UKIP. One even writes for a UKIP site/blog and gives talks to UKIP audiences where he describes the UKIP audience as "distinguished".
Maybe exmuzz swerving to the right is as a result of there being a perception that the left are to soft/apologetic on Radical Islam? I think Anne Marie Waters cited that as her reason.