Chastity is encouraged but it doesn't happen. There are an increasing number of Muslims having premarital sex, Islam is being reformed at an increasingly high rate.
FGM isn't discussed in Islam its not an Islamic issue, it's not in the Quran or the Hadith. Why would a Muslim leader need to comment on this when it's not specific to Islam?
There are Muslim leaders in countries where this horrendous practice occurs, they do speak against it but that won't deter a community from practicing something they've done for centuries.
No one integrates FGM into Islam...they just butcher these girls for their sordid cultural beliefs. There's a narrative of seeing their husbands as God-like, not in a worship sense but in the sense that they'll do anything to make him happy. Plus it's a pride thing for the men, they want to know they took her virginity, it's sick and many of these girls are encouraged or even forced to marry men who already have wives.
The tradition isn't as rampant as before, however it still exists. More needs to be done to educate these rural villagers as its them that this practice stems from most.