Current OF system is deeply flawed, and this, implemented in a right way, might help alleviate its flaws.
First of all, a fixed time limit is ridiculous. It's easy to keep OFdom if you have a faction with > 50 members, even if you don't do any RP at all after achieving officialdom. It's also really bad for balance between different factions.
And the fact that there has been repeated instances of half dead factions passing just by semi-AFK trading for time is sad.
Second, forum activity should count for something, but in game time should still be the primary requirement. Personally, I'd rather have a requirement that each OF has to organize at least one event where everyone (indies and opposing factions) can participate each quarter. Be it a skirmish, smuggling convoy, trading run, siege or whatever. Events can be simple and they should not need a lot of admin oversight or support with configuring stuff.
Third, the Forum RP is not the primary thing that will attract people to factions, but it might help with finding a couple of dedicated members who can keep the faction afloat without committing too much in-game time to it. This is still a light RP server and most people prefer to just do some simple trade runs with appropriate characters or quick pews instead of writing out pages and pages of forum stories.
But with this people who do spend hours and hours on writing stuff can feel they are contributing proportionally with their time commitment.
Still, even with this "band aid" solution, the main reasons on why people don't really want to commit their time to being productive members of an OF will not be solved. For that, the devs need to look deeply into the psychology of their playerbase, their behavior, and on the supposed benefits of being a member of an OF, as opposed to being just some no-strings-attached member of a casual group that plays together.