Unless they miraculously fix the atrocious server issues with lag/delay, crashing etc. that was experienced in the last ~2 years of Fallen Earth I don't see the point in bringing it back online even for nostalgic purposes unless you're fine with 10 server restarts per day because of it crashing/lagging out and losing items/progress.
Do it right the first time, fix it and port it to a new engine and give it a real chance at revival. You could cater to a lot of the indie community's if this game was fixed up properly and marketed right and get a 300 to 600 playerbase. This is the only game people mention when people ask for a post apocalyptic MMORPG even people who haven't played it. Game could be profitable if it capitalizes on the cosmetics similar to how APB has survived and focus on social media presence to passively advertise for the game.