HAR Gibb, Ignaz Goldziher, Joseph Schacht, W. Montgomery Watt, Patricia Crone, Marshall Hodgson, and Albert Hourani all spring to mind.

Among living historians: Robert Hoyland, Michael Cook, Ira Lapidus, Hugh Kennedy, Richard Bulliett, and Fred Donner all jump out.

My own interests are decidedly contemporary and 20th/21st century focused, so among writers/thinkers/historians/journalists who write about that I'd say Shadi Hamid, Steve Coll, Philip Khoury, Roger Owen, Eugene Rogan, Benny Morris.

As this is focused on writers/historians/thinkers working in Western academia and writing in English it obviously has a bias in that direction.