Separate the media hype from the actual issue. Samsung first issued the world-wide recall before any of the massive media coverage... it was the recall announcement that thrust the story from the buzz around tech blogs to making headlines on CNN, Fox, etc.
Before all this mess, Samsung still did their initial investigation and came to the conclusion that all of the Note 7s with Samsung SDI-sourced batteries were vulnerable to a rather catastrophic failure. They wouldn't have taken that drastic a measure unless there was a valid and pervasive threat. Sure, the media may have overreacted, that's par for the course, but that doesn't change the seriousness of the original issue.