Reddit mentions of Huck’s Raft: A History of American Childhood

I'm going to go ahead and strongly (if respectfully) disagree with /u/DomeesticatedVagabond. To chalk the decline in children's independent mobility (use this term to search) up to "false memories" fails to recognize a large body of international research on the topic(s). The difficulty lies in the question posed by the OP - which is actually a highly complex one, involving the changing construction of childhood. Here's a short version of the argument I make: children's independent mobility has fallen markedly in Western countries over generations, both in terms of range (mobility) and surveillance (independence). I attribute this to the larger "turning inward" of Western societies, driven by socioeconomic forces, leading to decreasing trust in communities and neighborhoods - exacerbated by mass media reporting on child predation. Below, I'll point to some of the sources I used or have read:

Immediately, I would point to the work of Valentine & McKendrick (particularly the literature review they outline in this piece), and the Policy Studies Institute publications One False Move and the 2013 follow-up. See also Kyatta et. al.

The geographers of childhood have long worked on these issues - follow citations of Aitken, Valentine, and Holloway for more.

Then there are the histories of childhood and play that use historical evidence to suggest a restriction of mobility, such as Mintz' Huck's Raft, and Chudacoff's Children at Play. More generally these histories place play and mobility within a broader socioeconomic context.

There's more research on parental fear and children's mobility - follow the citation chain through Foster et. al, Connor & Brown, etc. See also Nelson's great book "Parenting Out of Control".

We can also think about the impacts of increasing instrumentalization and adult organization of play as a factor in reduced independent mobility - see, for example, Hjorthal & Fyhri, and notably Karen Malone's "The bubble‐wrap generation: children growing up in walled gardens".

I'm running out of time on this post - but I also wanted to point towards the increased adult surveillance of youth. See more generally publications from Surveillance and Society.

Finally, outside of my disciplinary bounds, there has always appeared to be a literature on the topic from what looks like civil engineering/transport on the topic that I've never personally dug into.

I've got you on the "children not being well respected" side of things. From a socio-historical context, you have Mintz and Zelizer both arguing that historical changed to the family and industry have produced a different place for children in society. Basically, childhood was created and children are more a protected class, but largely at the cost of autonomy. I study childhood trauma and don't have anything on downplaying children's abuse, although Frones and Corsaro (part 4) talk about how the hysteria around children constantly in danger from strangers likely masks much mistreatment they actually treat, usually from people they know.

Well, you're wrong when you say "The age of consent in this context means that a 14 year old can have sex with people their own age." The "close in age exemption" applies to those who are 13yo or younger, not 14yo or older - at 13yo or younger they're allowed to have sex only with someone within 3 years of their age.

The age of 14 in Italy is the age of consent, period. Once people turn 14yo they are free to sleep with whomever they want. It's the direct counterpart of consent at 18yo in the U.S.

The concept of "childhood" and of someone being a "minor" is a social construct, as explored in the book Huck's Raft. Right now we live in the age of over-protectionism, with helicopter parents and children whose days are scheduled as much as a CEO's at a major company. There was a time, however, when children in the U.S. worked in factories when they were 14 years old or younger (and there are still countries today where that is true.) In ancient Greece, men would mentor boys as a matter of course, and this included intimacy.

Whose concept of childhood is the right one? Why is 18yo a better cut-off age than, say, 16yo? What is that opinion based on?

I don't begrudge you your opinion, but I hope you realize that it's based on a concept that is unscientific and some facts that you get wrong.