I have a 10 year old boy and I'm facing these issues right now. I'm also in Canada so culturally adjacent to the US and similar enough with regards to this topic.
I don't see child welfare agencies personally as a particular threat when it comes to this topic. Maybe they ARE more likely to get involved in cases of more free range parenting where before they weren't, but it doesn't register as a real worry.
The major difference I see between when I was growing up and now is that when I went out onto the streets, there were other kids on the streets. My parents didn't know exactly what they were sending me out to, but they knew that there as a general crowd of kids that would be out on the street until some point in the evening, and that they would all go home at around the same time, and that's also when you were expected home.
The draw of smartphones and video games as indoor entertainment can't be understated, but I can exercise some parental tyranny here and always kick him out of the house to go play like my folks used to do.
But there are no other kids out there. I'm sending him out into streets empty of kids.
To mitigate this I'm trying to nudge things in the direction of him and his friends forming some sort of after-school crew that finds outside activities to do together, undirected. There are other like minded parents that I've found that are also interested in enabling something like this.
On the subject of risks - I strongly believe that the role of parenthood is to mediate a child's exposure to the real trauma of a hostile, often absurd reality that they will grow up into. Controlled exposure to risk, to self-directed decision making in times where they feel like someone won't be there to help them out and they need to figure things out on their own, these are critical requirements in parenting IMHO. And all risk comes with some small chance of tragedy, and that's a burden we as parents have to bear: to expose ourselves to the emotional trauma of the possibility of our children getting hurt, however small the chance, so that they are able to grow into healthy well-adjusted adults.
I feel like I have to work a lot harder than my parents did to enable that exposure.