Maybe the age shows off and many got sick, but i don't think we got in the process of dying yet.
In december 2013, the original Fallout were the games sold the most, by the second digital games company worldwide.
There are many Fonline MMORPG servers, with 100-300 people connected in the same time, doing quests/PVP/PVE, spending countless hours crafting weapons and armors that they would lose in 10 minutes during the next fights.
The Fonline2238 modding tools were released last years, with gave birth to new servers. More people learn how to mod it, to make other servers, like Ashes Of Phoenix or Desert Europe, that take place in other locations and are better that previous servers. Those Fonline modding tools allow for 3D characters, that are easier to make than old sprites, which means far more possible new contents.
But Fonline is not much discussed here. There are many Fonline forum/website for it. There are even forum/website for team of specific servers.
There are ongoing incredible (or rather promising) Fallout mods currently in develloppement, with good hopes of release, like Mutant Rising/Van Buren/Resurrection, that make sure the Fallout player have new things to discover and enjoy. They are only discussed in the mod section.
Also, there are new TB top-down RPG games that allow a gameplay close to Fallout, and provides modding tools that could be easier to use and with greater results. (like Shadowrun returns, Wasteland 2, to name a few). So there are good chances to see in upcoming years, mods that try to emulate Fallout and attract new players.
Sure, after a significant number of decades, only video games historians (if they exist), will know about Fallout, but the process haven't began yet.
Considering the increase of TB top-down RPG kickstarter killers, i doubt the interest will die off during this decade.
I even think that another 17 years of Fallout 1-2 interest won't be that hard to get.
Not only the community didn't died off, but it is likely that Fallout 3 disaster gave players motivation to learn modding, to get Fonline servers full (Fonline was born after Fo3) to invest money on kickstarters.