Sloths have long, thick, sticky tongues covered in a carpet of tiny, rear-ward pointing spikes that they can pull leaves in with.
So the tongues are quite different from human tongues and likely much less "soft" to touch and more "rough".
According to scanning electron microscopy studies on the topography of a sloth's tongue, the following results were found:
> The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface.