Good luck to current masters with their Fallen Earth 2.0 project and great thanks to original FE devs and story writers (these back before 2002) - for incredible idea and realization of post-apocalyptic world.
I suppose i may spend some cash to pay for standalone single player version of FE game if such ever created, It would be the best way to get preserved certain stuff as I want to remember and return to it sometimes, and it is feasible. Lore is good, chain quest is there. I bet the number of FE players like me never needed multiplayer / pvp to enjoy the game anyway.
Few my observations of (few of many) what was gone wrong :
1. The faction system sounds cool from lore point of view, still it wasn't that much rewarding (ok, Enforcer consumables were really cool). Crafting, weapons, synergy ? Speaking of highly praised crafting - it could be better made already in 2012, especially if it was less dependent on PvP mats and give a crafter more personal / factional touch. It also lacked an impact of personal choices made in lore story quests. The original design assumed you need ton of faction rep to farm, so you could craft faction armor. But for most of late comers, it was obsolete piece, only needed a as one of possible ways to get GORE armor. But wait - even it became useless with GT armor intro.
2. GORE boss raids were one of few successful and good game features, and it was solid way to make some a credits for pve players. The was a synergy between GORE raids, Citadel and gathering of PvP mat (rothium). I think the best time for game was when all people hunted for GORE parts. Citadel used to be a great community hub. It was fine for like 2 years, game was alive. Then GORE weapons nerfed and DT weps/GT armor set added, it made all GORE-related stuff obsolete. As a result it killed a need to participate in Citadel raids, it dissolved end-game community over few territories. Sure, GORE weapons nerf while was anticipated for very long time, but i saw it also caused that many people left the game, who heavily invested real money into it.
3. DOME wasn't friendly to solo/pve players while it became a gold mine for others. Devs were fine with it, and generally they never care of what average pve players feedback was. I think the DOME over year of its existence antagonized another group of players, who couldn't complete even early stage of DOME.