Here in northern Mexico, I hitchhiked a couple of times in the early 90s, when I was a poor student and didn't have enough money to travel 100 Km. When I had my own car, I picked up people on the same road if I was riding alone, to pay it forward. That wouldn't fly now, because that region is rife with thievery thanks to government inaction.
I guess now that I'm older, I wouldn't pick hitchhikers even if there was no crime, because while most are just regular people having a hard time, a few were frankly scary.
On both sides there's a bit of eyeballing I reckon.
At a rest stop you can often chat to hitchhikers before they even know you have a car.
It wouldn't surprise me that in the US (particularly around major cities) hitchhiking is considered dangerous because, well, the US has severe issues with mentally unwell individuals on a scale that simply isn't present in other cities (e.g. the people who have basically fallen out of society you'll see on SF/NY subways; not merely homeless but severely mentally ill).
I would guess without having been there that hitchhiking in the more rural states would be fine.
I picked up hitchhikers last week.
I went hitchhiking myself two or three years ago.
I don't understand what's anachronistic about it at all.