Earlier quoted context omitted.
Or Microsoft are just terrible at classifying spam
One of the signals they use for classifying spam is people clicking "Report Message->Junk" in Outlook, so it's probably a constant battle with people who forget they signed up for something and call it junk.
Frankly, the vast bulk of the email in my Spam folder isn't egregious fake medicine and the like. It's mostly low quality mailing lists, much of which isn't much different from what ends up in my inbox.