I do not have to respect anyone, they have to earn it.
I do understand Islam, that is why I have no respect for them, or Charles Manson.
Evil is as evil does.
What you might be considering less is that NOBODY is living a Mohammed-grade version of the thing, and that everything livable that is called Islam has been expurgated at least a little.
Ordinary Christian enlightened canons of decency can apply and will sift out the worst “Islamic” believers on grounds that have nothing to do with religion. Ramadan is a business challenge, but if the person has reasonable privacy, he or she may well eat anyhow on the QT (and still join in the evening feasts). I’ve met a number of people claiming Islam who were very reasonable people and didn’t use Islam to beat on other people with.