You’re both wrong. I’ve worked with some of the people who invented these products and still had to double check your reference to make sure I was correct. I was—Milken didn’t popularise mortgage securitisation. Ranieri did.
Milken did not ”[popularize] mortgage securitization”. Ranieri was at best his contemporary; he was not inspired by Milken. Your own article is a good source on this.
> read the article
I recommend Fabozzi’s Fixed Income as an introductory text if you’re drawing the (incorrect) conclusions that you are from that FT article.