Right now I can double-click an icon on my desktop that launches SimCity for Windows 3.1 inside of dosbox, and it works great. It didn't take much effort to get working, either.
I can't say the same for most dead FOSS that I've tried to resurrect. Usually I'll have to manage the outdated dependencies somehow, perhaps by writing a SHIM or somesuch; and probably significantly fiddle with the build system because Linux systems have changed significantly since the mid-90s.
It's a difference of hours versus days of effort. I've done both, but guess which I simply _haven't the time for_ now? I've got family and friends that need my attention moreso than a dead piece of FOSS no one but myself seems to care about.
But if you wanted to, you _can_ update dead Foss. Can't update that copy of Simcity, can you. Nopers.
Summarizing, closed source projects die. At best you can run them in an elaborate museum (emulator) and at worse, you can attempt to Frankenstein's monster them by injecting DLLs.
Open source will outlive us all.
How many places does Doom run?
Doom is a closed source game that was finished, polished, and then open sourced. Strange to use that as a FOSS example.
The FOSS-from-the-start examples would be Tux Racer, 0ad, and so on.
With the emulator, first you need to write that emulator, and then you only get precisely that version of the software. After that, you're toast.