The MSN brand is going to eventually go away soon. They stopped generating new "content" for the MSN portal some time ago, it's all farmed from other sites and sources now. Microsoft is focusing on their Bing brand instead. They even renamed their ad platform from MSN AdCenter to Bing Ads. I haven't had an MSN account in years, but only signed up for mine back in the early 2000's to get some discounts and other promotional offers. I never used it.
However I did start using my Live.com email account on occasion when signing up for trial offers and stuff like that, where I already used my Gmail account once for them and needed a new email to use.
Gmail is my primary email address these days, which is funny because I've actually had my own domain name for over 12 years now but I don't even use it as my main email address.