Obviously, he is not interested in being just a friend but want to be more than that. So your conclusion is wrong, you can't be his friend unless you are willing to become his boyfriend/girlfriend.

Well, it’s on him for not telling you about the crush (assuming that is the case). If he did tell you and you didn’t reciprocate, it’s also on him to move on to with grace even though it hurts. I’ve been on the receiving end of unrequited love in a similar situation. Give him the space he needs because he’s working through his emotions. If his friendship with you is really important, you then he will bring you back into his life. A true friend will be happy for you and want you to find happiness even if it’s not with them.

It may have been difficult for him to see, so he blocked you. Either he gets over it, or he doesn't. Just get on with your life.

Depending on how close you were, maybe he should have explained it before blocking you, but other than that I don't think he did anything wrong. Emotions aren't decisions. I've been there. If it hurts him to see you with someone else, that's just an unfortunate reality, and if so, trying to be friends could very well be a disaster for you both. Be mature, and try to part on the best terms possible.

That's on him, not you. It's best to accept his decision and move on.