Too much stressing in this thread. I flew home to the US the day after surgery with Dr Pinto - 8 hours. It's really not a big deal. Few things:
I wouldn't worry about wearing a hat - nobody will stare at you. I even went through a pre-flight Covid test and the nurse who stuck a swab up my nose didn't give me an odd look or anything.
Don't worry about spraying your grafts during the flight, you don't have to (Pinto will tell you this himself). I didn't spray until I got home, and my hair grew perfectly.
Window seat is probably ideal but it doesn't really matter. Really, how many times have you ever bumped your head on a flight? Probably never.
That's it, it'll just be a normal flight. You'll be fine. No need to stress about anything, especially since you're going to Pinto, the surgery itself will be a breeze. Try the chicken sandwich from hotel room service, it's pretty good (comes with fries).