Your answer will depend much on your camping habits. If you camp in pounded and depressed areas (as found in many campgrounds), you need to be very careful about a ground cloth. If you camp on well-drained higher ground (like much "dispersed" camping on public land), you don't need one at all.

I haven't carried one in over ten years, and the two tents I've used in that time frame, both with very light silnylon floors, saw hundreds of nights of use, many of those in desert and high rocky tundra, and never had floor damage. And after I learned to identify good campsites, I never got wet.

Of course you can carry a heavy sheet and not worry about it. But sometimes it's a matter of substituting care and experience for gear.

With the tents I use, I'd rather deal with a single dirty wet tent than a dirty wet ground cloth plus a wet tent--one less wet thing to pack and dry out later.