I personally think uncut is better as it looks more natural, and is probably better for bees and other insects. The flowers and other weeds that grow make it look nicer as well.
I don’t think cutting a lawn is that bad as long as its not done too often, though.
edit: grass. This is a post about grass.
Edit: Lawns, like the grass in your lawn, jesus christ.
Uncut. Those pre-sliced sheets are handy, but they’re either too big or too small for the present you’re wrapping, and you end up wasting more.