its been alluded to with his business partner that hector killed.
No, it wasn't man.
I can tell you exactly how this rumor started. During a podcast Kelly Dixon, an editor on the show mentioned she thought they were a couple. Vince Gilligan said "nah, that's his brother".
Not literally his brother but it was the podcast after the episode "Hermanos". Gus and Max were best friends.
Directly after the podcast the rumor was all over the internet, despite the guy that actually created the characters flat out saying it was false.
Giancarlo Esposito got asked about it and was
because he said it was never mentioned to him, wasn't in the script, was never even brought up as an idea.
So nah, he's not gay. They even had an arc that would've went into his family, kids, etc. but they didn't have time to add it.
Fred.