Yeah I don’t think there is any comparison in how much more superior the US is when it comes to long 500-1000 mile relatively accessible trails. I can think of 10 just off the top of my head.
The Camino is vastly superior, just in a very different way.
ETA: I shouldn't say it's vastly superior, rather the Camino is a very, very different experience from the trails alluded to here, and is superior in relation to that experience.
Él camino de Santiago is actually an ancient pilmigrage route,
It has some variants but the main one has a lot of traffic and it's not rare to make friends as it's a very social route.
And there a still a lot of people walking it for religious reasons (to a varying degree). It is actually a whole network of ways that spans most of central and western Europe. So you can meet pilgrim quite frequently at some "choke points".
I loved thinking about people 500 years ago walking on the same stones I was walking on, and thinking about what the exact spot I was currently standing on was like back then. What did it smell like? What did you see? Were the fields this open or were their more trees? Did you run into a lot of people?
ETA: I shouldn't say it's vastly superior, rather the Camino is a very, very different experience from the trails alluded to here, and is superior in relation to that experience.