The highway has been very useful* with Tesla's FSD for the 4 years I've had it. That's actually at least a couple of orders of magnitude easier than city streets.
Before (V11) it would work on surface streets but not all that well.
Now it actually drives successfully and maybe will improve very fast. It's a guess but I'd now say that the other ADAS systems will never catch Tesla. Ford may well be the first to licence it.
* but sure not something you can relax and ignore -- far from perfect. I'll be interested in how V12 does on the highway but don't get out of the city much.