I wrapped a collector once, really close to a transmission pan. So close you had to clock the collector bolt to clear the transmission. Was running aluminum collector gaskets which worked. The unwrapped side was just fine. The wrapped side melted out the aluminum. Won't run any more wrap after that.
Had a talk with a co-worker about it the other week. If you are doing an all out race car, disposable parts after a race or season, need every trick part possible, go ahead and wrap. Expecting a good long life on a daily driver or weekend toy that you don't want to always be rebuilding, don't wrap.