Nobody Reads Press Releases
Google Is Over Them
User Engagement
Online press releases are basically walls of text with a frigid Call-to-action at the bottom. On most sites, user engagement isn't even incited and usually not even allowed.
Publishing through Medium, BuzzFeed (yeah I'm brown-nosing), Reddit, or even Tumblr encourages users to ask questions, leave their criticism and share your post with other community members. A company that seems like "one of us" goes a long way with the anti-corporate Millenial.
You Have The Freedom To Create
Publishing through a Press Release service or traditional news media may include a style guide to be strictly adhered to. That is definitely not the case with blogging & social media.
This sort of freedom allows you be interesting, creative, spunky, and even use non-professional language. Of course, following the sites' rules (like no racism) is still required.
Conclusion
I think it is time to ditch traditional media outlets as future generations will only be more Internet-connected than ever before. Just like Television, and then the Internet, has obliterated the printed newspaper, the Web Release will triumph over the Press Release.