Confirmed that MFA is now an option under My Profile -> Password and Security Settings. And its not just email MFA, looks like there is proper push via app as well as text. I only enabled the email MFA so far, and can also confirm it does not challenge every time like one would expect. Haven't tried the push notification via App yet, as the whole login / password configuration on the Delta web site is very picky and likely broken. Every time I try to change my password, I get the error that cant use same password as last 2 when clearly I am not.