No, because the spell says right there that it can only affect up to five creatures. The spirit of the spell says that it can't do twice as much by just piggybacking on something else. But if you have 6 or more people in your party, this can feel like a small problem with the spell. In this situation, I think Feather Fall should be able to be upcast to affect one more creature per spell slot above the first. There's no reason not to let this happen.