Interesting indeed, just a shame the YouTube videos are of such poor quality the text is unreadable... I have no idea what they were supposed to be showing other than Defender is somehow involved
There is also no mention about which versions of SMB are vulnerable... I've made it a habit to disable SMBv1 on Windows 7 for several years now, does this now potentially include v2 & v3 as well? (not that i'll be disabling them any time soon).
Running Windows 7, I don't of course have access to Defender however I assume that Security Essentials is equally as vulnerable?