How diverse are the contemporary praxes of Islam?

I mean from a scholarly perspective, not advocating what proper practice is, but how different contemporary Muslims are from each other, and in what proportions. For example, what estimated percentage of Muslims say they believe the Qur’an is to be observed word for word, vs. those who believe in lenient reinterpretation? (I know one person who has attained some level of position in their mosque, maybe an imam, who said “You have to keep in mind it was written 1000 years ago.”)