I think the whole "10 mile" thing is designed to keep people closer to home, avoiding trips that could burden first responders (i.e. a bunch of people go hiking in the mountains and get stranded, resulting in rescue crews spending time on them rather than those who are sick). But then again, I thought most accidents happened within a mile of your home, so... I don't know...
The 10 person thing is definitely more social distancing - keeping large groups of people from gathering helps slow the spread of the virus.
That's my take on it, at least.