I see a "2010 GOG Edition" version as well (the only other GOG release for this particular game), but the one under the list I posted above is shown as "2024 GOG PP Edition" and has separate versioning (i.e. the 2010 release's final version is notated as 2.0.0.9 from about 5 years ago, while the 2024's is 1.0.1.0 from a few months ago). What "PP" might stand for, I do not know, and Google doesn't seem to give me any relevant results. "GOG PP Edition" is a funny name, though, which has to count for something. Given that there was a previous GOG release, it probably shouldn't really be included in these results, though.
(e): Oh, duh, "PP" is the "Preservation Program" GOG started not that long ago. It's basically their own souped-up version of the game that's supposed to ensure that it can be run on modern operating systems. So yeah, definitely shouldn't be included. I wonder how many like that are in my list...let's check: four. They are RollerCoaster Tycoon 2, Caesar III, SimCity 3000, and I Have No Mouth and I Must Scream. Okay, so not as many as I expected, doesn't really affect the results all that much. There are more games in this Preservation Program than that, but those four were apparently the only ones that changed significantly enough to warrant the separate/distinct release year notations from any previous releases GOG might have had of them.
Yeah. If nothing else, I would not want to see what these lists would look like for Steam, as I'm sure the GOG lists must dwarf the Steam ones.