In the end, I think we can all agree that Quran is the only absolute in Islamic faith. I'm saying this because there are people who reject the Hadith. But throughout all sects, Quran holds majority of the influence. Then comes the translations and tafsirs or interpretations.

You are right, the practice is of the Islamic faith is not consistent across different cultures and countries. But, even if people don't follow it properly, it does not negate what the Quran has set in stone. It does not abscond the many questionable verses that exmuslims and critics like to cite. Verses that Muslims will interpret (either to favor to the moderates or extremists). The Quran itself will never "modernize". Not in a thousand years. That is how powerful of a book the Quran is.

I think the issue exmuslims have with hypocrites (People who don't follow X of Quran, yet call themselves Muslim), is that they bludgeon you with their beliefs. They are still Muslims, IMO. Just very shitty ones. Its human nature.