My eye's aren't closed at all, I'm simply never going to experience these types of network delivered malvertising attacks because by using ad blocking I've cut them off before they can ever reach the browser, which is currently the only effective way to guarantee you'll never experience them.
It's a nice thought that Microsoft or others with popular destination pages might mange to break a malvertising supply chain, but that takes time and until it happens you'll continue to experience these attacks if you're part of the malvertiser's target. In case you hadn't seen it, some of the articles discussing that earlier Kovter attack mentioned that these used a number of filters including ISP, fingerprinting of the timezone, screen dimension, language (user/browser) history length of the current browser windows, and unique id creation via Mumour, to target users and evade analysis.
The fact that MSN was affected is itself insignificant, since anyone using the primary ad network through which the underlying malicious network was fed could have been affected. Remember that there isn't a single layer of these, it's actually multiple layers of networks feeding networks, so finding the true offender is a needle in a haystack and whack-a-mole problem.
Just as with my own confusion with multiple settings and other changes to security I've made over time, you appear to have added confusion relating to Windows Defender configuration changes you've made as well. How these may be affecting your specific configuration(s) is unknown and though these may have no effect on what you're observing, that's impossible to know without starting with a clean Windows installation.
I don't deny that you've learned some potentially valuable details, I only feel that consumers require a simpler and thus more foolproof approach to protect themselves and especially others like children who use their PC in the home.
Rob
< EDIT > The question of the use of exploits or simply social engineering as appears in this case was being discussed years ago; Malvertising Could Replace Exploit Kits: Researchers.