Youtubers regularly swap the video thumbnail + title. Youtube even has tools to A/B test various thumbnails + titles nowadays for different users.
I can confirm that the title "I Hacked My Friend's Phone to Show How Easy It Is" was the actual title when the video was uploaded. However you're right that it now looks like it changed to "Exposing The Flaw In Our Phone System" a day later.
I can confirm that the title "I Hacked My Friend's Phone to Show How Easy It Is" was the actual title when the video was uploaded. However you're right that it now looks like it changed to "Exposing The Flaw In Our Phone System" a day later.
Watch an older Veratasium video about Youtube's title+thumbnail clickbait: https://www.youtube.com/watch?v=S2xHZPH5Sng