But there was no outright ban. Well, except for those countries who expelled their mulsims, but that did require a larger muslim population to begin with. As it was, Muslism would not be received well in most European states, and before Enlightment hit wouldnt be able to build mosques or anything, but being Muslim itself was not illegal in the majority of states.
We agreed that the term was one of convenience to describe a more or less pan-European phenomenon that differed in detail from place to place.
If being Muslim was not in itself illegal in much of Europe, this was because it was irrelevant. There were simply no Muslims - they were not welcome. That is why much of the Ottoman diplomatic corps stationed in Europe was Greek or Armenian. And it was illegal in many places. The terms of Serbia's autonomy, for example, was that Muslims were banned from settling there.
I find a lot in the Wiki article about Islam in Germany dubious. I don't doubt that there were a handful Ottoman Muslims serving in the Prussian army, but a 1,000-man Bosniacorps in 1760? Have you ever even heard of such a thing? It would have had a large impact on both Prussia and the Ottoman Empire.