PS4 2-Step Verification quite some time ago, today Sony rolled out two video guides on adding a mobile phone to your PSN account both from the PS4 and from a Web browser for increased security (unless someone does a SIM swap or SMS intercept without getting caught) and recovering your password should you ever need to.
Also below is a video from Sony on Software Engineering as part of their PlayStation Careers campaign for those considering a career in the field... it wouldn't be the first time someone got a job at $ony and then shared a bunch of 'insider goodies' with the scene despite signing their NDA papers.
How do add a mobile phone to my PSN account? (PS4)
How do add a mobile phone to my PSN account? (Web)
PlayStation Careers - Software Engineering