I believe Microsoft is working with spammers. I have a public facing Outlook email for a specific reason. Naturally, I get a lot of junk mail in that account. Whenever I create a "rule" to filter out junk, within a very short period of time, sometimes less than an hour, spam appears set to go around that filter.
For example, I get some spam looking to get me to sign up for Obamacare plans. I create a new rule that says all emails with the text "Obamacare" in the subject go to the junk folder.
Later that day, I will get an email with the subject "O.b.a.m.a.c.a.r.e." However, that often doesn't happen when I don't create the filter.
Many such examples.
Of course, the email comes from [email protected] so blocking the sender does no good.
So, it's possible to see the delivery status of an email using certain software.
If a scammer sees their messages going to junk, they may have scripts set up to try to take what you are blocking based off of, and then modify their message accordingly. Spam is a numbers game, and automation makes it a much easier game. Plus scams constantly evolve with technology, they probably have a team dedicated to avoiding spam filters. Otherwise they won't make their money, and they do male a surprising amount of money, otherwise they wouldn't do it.
Should I just delete it, report it as junk, or move it to the junk folder?
I would probably report as junk and move to junk folder too.
Believe it or not, domains and email addresses have trust scores associated with them, and the score goes down a bit after each report until eventually the email just gets delivered to spam automagically.