Then over time developers built neighborhoods and the population exploded, so as the population grew the roads had to be expanded. Traffic planners had to move people somewhere, and they compensated for the wide streets with 20mph school speed limits, volunteer crossing guards, extensive education of children and drivers, and regular active enforcement of the school speed.
So the article comes across as clueless, seemingly almost deliberately so to exploit a tragedy.
As for the 20mph speed limit - besides the fact that he specifically says they are irrelevant, since drivers don't respect them -, how would that have helped, considering it was 8:30pm when the accident happened? And I'm betting the "volunteer crossing guards" weren't around either. Apparently kids sometimes leave schools outside "schooltime" - who'd a thunk it.
Finally, if we're talking about what he left out - maybe you should add the other detail he didn't mention: that there had been already 15 accidents in the crosswalk in question in the last five years. So maybe it should have been clear by now that the methods weren't working.
(By the way, "the population exploded and the streets had to be expanded" is false. Governments have tools to control the growth of the population, like permits and zoning.)
The article is blaming all the wrong factors.