True SPAM .. fake SPAM .. good intentions SPAM .. if it wasn't requested, or wasn't from someone or some company you correspond or do business with, it is SPAM. You can treat it how you wish.
I said above that I expect it, admire companies that adhere to the conventions of opting in for future contact (or at least making it easy to unsubscribe), and loathe those that do not.
I agree the more insidious stuff is the crap that comes by the boatload from spoofed IPs, ficticious accounts, compromised accounts and bots.
Even a relevant business solicitation, the first time sent, is SPAM .. until YOU decide its merit.