You are proving GP and OP’s point. CS 1.6 was an exceptionally popular game in the GoldSrc days and that is why it survived and was chosen by you as an example. That is an exception not the norm. Plenty of FPSs from the same generation have been forgotten. How many people out there are still playing Day of Defeat? Or Counter Strike Condition Zero? Or any of the old Delta Force games? Or Daikatana (except for the lol factor?)
I don’t even think you can easily find people to play on pre-1.6 versions of CS these days, even though when I played CS on LAN I had friends who believed CS 1.5 to be the better version and insisted that we play that instead.
I think the Starseige Tribes community is still active. They have DOZENS of people, dozens!!
Not to hate on those who love old games but yeah, it's a much smaller community.
It's not all bad, smaller communities mean people know each other better. And there is no eSports money hanging over anyone, it's just a community meeting up to have fun once a week.
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The only reason Starseige Tribes is alive today is because of a large amount of hacking effort to port the game up from Windows 2000 to modern Windows. As well as hack the server software to run you own servers.
Other live games truly die. No one will ever play Concord ever again. Tribes loses support, but hackers can fix bugs and forcibly patch to modern systems
There were also lots of exceptionally popular games that didn't survive simply because subsequent games were simply better. One example there would be Street Fighter 2. So the difference is that I'm arguing that games have staying power based on their overall quality, not their quality for a given era. When they're reasonably objectively surpassed, they tend to die off. If they doesn't happen, they tend to stick around.
This is true in modern times as well. Skyrim, for instance, remains a best-in-genre game that (like Counter-Strike) even its own creators are failing to surpass. And if it's not surpassed in the future then people will probably still be playing it in 20 years. By contrast if it turns out that the next Elder Scrolls game manages to take the same formula and just make it better, then Skyrim will probably gradually die off.
I don’t even think you can easily find people to play on pre-1.6 versions of CS these days, even though when I played CS on LAN I had friends who believed CS 1.5 to be the better version and insisted that we play that instead.