Muslims had very different expirience of applying Islam, golden age of Islamic Khalifat were the first centuries of it's existence(tho, Islamic Khalifat in it's strict sence existed for only about 30 years or so)
Muslims were most sophisticated and progressive when they were very religiuos, when they abandon Islam and put in merely on an individual level, muslims've become backward and regressive and weak as of now.
Europe on other hand had very different expirience with christianity, which quite the opposite, that's why when you relate to Islam and muslims having historically europen expirience as your background you can make some grave mistakes, muslims simply have different paradigm, it's a historical fact - fully embrace Islam = prosperity, progress; abandon Islam = backwardness, regress.