I don't really disagree with any of this. He shouldn't have done what he did, it is obviously threatening and hostile behavior. At best, it's an incredibly stupid thing to do for any number of reasons, at worst it's pointing out "I know where you live" to someone as a direct threat.
The question is how do you respond to such a threat? I would personally feel more strongly about it if a written threat was actually made in the note, but it doesn't seem like that was the case. A list of demands and a plea for dialogue doesn't really move the needle any further for me. It actually moves it backward a little for me because it indicates, at least to me, that he's just a stupid college kid that decided to try and make himself heard in one of the dumbest possible ways rather than someone who would actually try to harm someone.
I've quite literally had strangers come up to my house and yell at my goddamn doorbell camera in the middle of the night before (sorry Rex's mom, I just don't love you anymore), but I never felt the need to call the cops on them or pull a gun on them, so what does that leave us? Despite the attempts to characterize it as a home invasion, it clearly was not and I doubt any laws were even broken. So again, where does that leave us?