As a man who is bi - I frequently run into guys that are not comfortable with me showing them any kind of affection or hug or compliment even.

I disagree that this can be toxic - I believe that with him there is a boundary he has set - and while it is pretty close to his chest or maybe far from his chest - honor that and honor him and his request without being offended.

Be a friend and accept him for who he is even if he has an issue with who you are - we don't have to be 100 percent compatable in everything to have a great friendship, and just remember there are plenty of guys out there who really would like a hug.