Ahh, but while Islam is many things, a good many of them negative, it is not idolatry.
Idolatry refers to the worship of images. Islam, which is quite literally death on images, by any reasonable standard is therefore less idolatrous than most variants of Christianity, which usually have images, statues, crucifixes, etc. that are show special reverence.
Now one may expand the definition of "idolatry" to mean any false worship, even when there is no physical idol, but that is IMO stretching the definition beyond a reasonable point.
What is that rock, dressed in drag, in mecca, called again?
Idols and false gods are interchangeable to Christians. Any false god, whether he has a physical object representing him or not, is an idol. They can’t think, they can’t speak, they can’t hear, and they can’t answer us. They are created by the minds of men, rather than their hands, but they are still an idol fashioned by man.