I have carbon FBF cans, and in 8 years have noticed no issues on my bike with header wrap. I like the way it looks, and it keeps my little hands from getting burnt. And my headers looked like crap, which was why I did it in the first place. Doesn't seem to make a bit of difference in how it runs at all. And it so far has held up fine for the cost and effort involved (low and very little), needing replacement only once about a year ago. So, from my experience on my bike the wrap just looks cool and hasn't hurt, or helped, any other part of the machine in the process.
Cool (..!) I'm thinking that perhaps the likes of a 996 , despite being liquid-cooled, must pump a lot more heat down the tubes than our geese ever could ... glad to hear that you have had no issues then.
Gio