Specifically, to document the memory-map each one used.
Traditionally, SNES emulators have used the internal game header and a whole stack of heuristics to guess at what memory-map each game expected, but that's not exactly what you'd call a preservationist approach, and caused problems for homebrew that wanted to set up a perfectly legitimate memory-map that no commercial games happened to use. Now there is (or there will be) a standard database of game SHA256 → known memory map that SNES emulators can use, and a way for homebrew games to explicitly specify what memory-map they want.
Traditionally, SNES emulators have used the internal game header and a whole stack of heuristics to guess at what memory-map each game expected, but that's not exactly what you'd call a preservationist approach, and caused problems for homebrew that wanted to set up a perfectly legitimate memory-map that no commercial games happened to use. Now there is (or there will be) a standard database of game SHA256 → known memory map that SNES emulators can use, and a way for homebrew games to explicitly specify what memory-map they want.