If we're talking about isopropyl alcohol, I don't think I've ever seen it react with ABS. Goof Off will melt ABS, tho.

Magic Eraser / melamine foam should be a last resort as it's the equivalent of 3k-4k grit sandpaper. Most SNES-era carts should be gold flashed and abrasives should be avoided if possible, including MF, Brasso, and similar compounds. It's not that it will make them stop working, but they may end up needing more frequent cleaning in the long run, depending on environmental conditions.