Your suggestion for centralizing and managing events is to decentralize and maintain posts on multiple sites? Interesting... This approach doesn't scale well at all and, without going into the past, led Indiana to where it is today.
Personally have always felt that the organization a forum provides is infinitely superior to any of the 'social' media platforms. On a forum, you can go to one page here and see everything posted currently for the state of Indiana. Then you can go here to see everything outside of Indiana. Seems to be a ton easier than stopping at Facebook, Reddit, Instagram, pinterest, Twitter, <insert other social media here>. Trick has always been, as Joker mentioned, getting people to actually go to the links (and people to post their events as well).
From an EO standpoint, a singular post on a forum that I link to on other 'social' media platforms is drastically easier. I can update game information and rosters, answer questions that will be posted in the thread so "in theory" others could read the thread and not ask the same question, all while saving me as the EO, TONS of time not having to duplicate effort across 10+ sites. I digress...
Anyways, the new release of the forum's software does indicate the ability to log into the system through the use of social media accounts such as Facebook, twitter, stumbleupon, reddit, and even LinkedIn (this one seems odd to me). I haven't had a chance to mess around with it yet but it was recently posted to their page. Not sure if it'll help with the "distribution" or not but maybe it'll make the extra click easier to bear for the younger generation?