After all this time, all these spams, all the complaints from all over the globe, I can only come to one conclusion: Microsoft is trying to kill email.
Let's take a look at some facts. Spam levels are as high or higher than they've ever been. From my own personal experience, I can say without a shadow of a doubt that 99.9 percent of all email coming to my mail server is spam. That's tragic all by itself, but it's been that way for quite some time now. I have written and documented the severe steps that I've taken to reduce the problem, but the fact remains that hundreds of thousands of connections are made to my mailserver every day, trying to sell me v1@gr@!, inform me of my incredible good fortune in some foreign lottery, or tell me that really need to buy stock in some company nobody's ever heard of.
Hundreds of thousands of connections, coming from thousands of hosts. What are those hosts anyway? The vast majority of those hosts are exploited Windows systems. They're zombies run by botnet operators. Their owners are probably completely clueless to the maelstrom that has engulfed their little Dell desktop. It's just "slow".