Useless seems like a strong word. I tried it out for a trip and I think I only had to intervene once when it phantom slowed down on the freeway. I've had other cars whose lane keep required a lot more intervention.
The Tesla changed lanes to faster lanes, could navigate itself off the freeway, and it wasn't until I got into back roads without lines and stuff before it got a bit iffy. But even then it did a decent job navigating.
I'm not aware of any other systems that can do that.