> I feel [children] already are [safe] on neighborhood streets
Much of Seattle's neighborhood streets don't even have sidewalks or traffic calming devices. 25mph is a suggestion, at best, when people are trying to get around the lights on Aurora, for example.
> I've personally heard public transit horror stories from friends several times...
The plural of 'anecdote' is not 'data'. You already seem to dislike public transit, and may surround yourself with people who feel similar. Could also be confirmation bias.
TL;DR driving would be lovely but for the other vehicles. :)
> limited to 25 MPH in the US
I'm more thinking of traffic calming such that there is planting and chicanes to ensure no line of sight, equal priority, and drivers naturally tend to dawdle at 10 or 15mph along like they might if driving through a town pedestrianised high street.
A city centre night out or shopping trip is far nicer when the streets have been pedestrianised, and there's no traffic except the odd service vehicle and public transport. Sitting outside with a coffee is much more pleasant without the taste of fumes.
> Highways and arterials are not where children
No they're not, but you have to get to them, which is where a lot of problems arise. At that point I may as well get to the railway station instead of the highway. Except thanks to lobbying and politics, that's comparatively neglected, so not as appealing as it should be.
But it doesn't have to be this way. I think that depends on the particulars of the city. Seattle, for example, has been very drivable until the city enabled a large population influx in the last 5-10 years, undertook significant upzoning, and simultaneously purposefully degraded driving infrastructure (unnecessary reductions in speed limits, for example). I would say medium-density cities can be very car-friendly rather than frustrating, if they avoid trying to make one large city-center and instead aim for something more distributed with several smaller centers.
> The sooner we get back to streets safe for children to play in, the better.
I feel they already are on neighborhood streets, which are almost always limited to 25 MPH in the US. Highways and arterials are not where children are expected to play.
> I won't play tit-for-tat with equally emotive and useless links to stories about people having watches and wallets lifted at lights etc.
While I do not have data on hand, I'd wager that watches/wallets lifted at lights are rare compared to robberies/assaults/harassment at bus stops or on subways. I've personally heard public transit horror stories from friends several times, but never something similar in their car.