I rarely see the electrolyte get very far from the capacitor, so I’m guessing that it wouldn’t be an issue. Once it dries, it can be hard to remove, but since it rarely makes it far beyond the capacitor itself, I haven’t needed to wipe it up. I’m also a little afraid that using a wet paper towel might just spread the stuff further around and cause a short, but I’m not sure. The biggest issue could be the fact that the capacitor itself probably doesn’t work, which might be problematic if it’s in a PSU or similar.

Since the oldest hardware I have is from the mid-90s, I suspect the problem would be more pronounced in older machines and a re-capping job might be warranted then.