There's no reason why nylon strings wouldn't sound alright on a regular steel-string acoustic, but getting them there may be challenging for a several reasons.
1) First off, nylon strings are typically tied off to the bridge of a classical guitar. With no ball end, I don't know how they could be anchored to the bridge of an acoustic. Perhaps a no-slip fly-fishing knot like the "Perfection Loop" tied at the end, would give enough bulk for it to bind tightly against the bridge pin ... don't know.
2) Second, the small diameter of the typical tuning post on a steel string may be too tight a turn for a nylon string ... might stress it to the point of breaking?
3) Third, the slots in the nut are cut for smaller gauge steel strings. Unless the nut was re-cut, the nylon strings would sit quite high off the fret-board, and may not even stay seated in the nut very well.
Probably not a practical idea, and if a person modified the guitar enough to accommodate nylon strings, it wouldn't be suitable for steel strings afterwards.
Just my .02 cents worth ...