IDK about you but i plan to keep playing FreeSpace for at least 10-30 more years D:
It's just so great, and as you said, new stuff get released. Plus there is all the old stuff to do

Of course there's a high probablity the game is going to be overwhelmed by games more efficient, with better graphics, stereoscopic 3D, blur, etc (eg. TrackMania has those 3) in some decades - but as far as i can tell, there are less and less space operas and sims being released (i might be wrong though).
Know of any good space sim fighting as realistic yet fun better than FreeSpace ? i searched for quite some time and haven't found anything like that so far...
One major force of FSO is that it's being ACTIVELY modified and improved, which AFAIK is not the case of traditional commercial games, where they just do small patches and bug fixing (as they develop other stuff at same time)
As long as it keeps being upgraded, it should be able to live on no problem imo.
I would add too, it's mostly a SOLO games with heavy immersion and stuff, which makes it really attractive imo.
Also allows modders to continue adding scripted features, workaround, beam-piercing effects and idk what shiny stuff.
A game like FreeAllegiance, that is still being upgraded (even though i guess

less than FS) followed the same kind of history but has only few people playing it, since it's mostly a multiplayer game.
And even if the SCP team would stop NOW, the game and community would at least keep being active for something like 10 years, i guess, especially through modding.
I get the feeling FS2 will stay active much, much longer than MMOs like EVE Online for example
