It does happen that people revert or embrace a religion after being atheist for several reasons, one of which is to get with someone. It's a path that may start with personal gratification. Religion is personal too. Maybe the quest for the truth has finally been fulfilled.

You and I see eye to eye on your last statement. You cannot stamp a born Muslim with quality-assured while rebuff reverts’ faith, on the basis that the former was born to Muslims, or have been a Muslim for longer.

Salaam