I'm going to give you an honest answer, so be ready.
There is no correct answer to this. Some people will say, "Yes. The desiree to see another man without a shirt makes you 100% homosexual. To see a man naked, you might as well start crossdressing."
Other people will say,
"Hell no! That doesn't make you gay! I have bareback sex with this guy at my gym every week, sometimes I like him cum on my face, but that's not gay because I say it's not gay."
Some will say it's just that you're curious, some will say it's bonding, you'll be driven in different directions.
Personally, I think just masturbating is more of a... bonding thing. Masturbating eachother is a little different, but what do I know?
I will say this, my best friend and I have been masturbating eachother for the bast 5 or 6 years, and it's been the most fun we've had. I would highly recommend it.