My recollection is that it's merely a different generation, perhaps including bundled/pre-installed updates.
This is just like there are multiple generations of cf installers also. Adobe doesn't create a new installer for EACH update, of course; but after a few-to-several they typically have created a new one. I've tried to keep up with those different versions in the cfmlrepo site.
That said, do you really want to use that old cf builder 2018? It's no longer updated, to be clear. More important, that was the last of the versions built upon Eclipse (as the core IDE platform).
Since Aug 2022, Adobe has offered CFBuilder only as an extension for the far more popular VSCode editor/IDE platform.
Also, both vscode and the Adobe cf builder extension are entirely free, unlike that old CFBuilder which operated on freemium model.