If you take all the subsequent story built around him, yeah for sure. He is a well written character whose actions make a lot of sense honestly.
Also I like the "theory" that he never slept once in all his time studying in the mansion. He literally stayed awake for days, weeks... however long they were there. That's why he becomes more and more unhinged as he reads. First just the reality of who/what he is, the rage at basically being a company experiment, that he gave EVERYTHING of himself, killed his only friends, all for a company that made him a science project. Then, you don't sleep for like, weeks? Just stewing in what it all means? Eventually he just kinda snapped which is why when seeing it from Cloud/Zack's perspective, he goes from being annoyed and angry to homicidal. He snapped.