" namely that people should care equally about every casualty, regardless of circumstances or causes, "

Where did I do that?

A thought experiment - how does your reaction to "cyclist on sidewalk kills child on bike" compare to "driver in street kills child on bike" ? I suggest they should be the same.

I understand we may simply have utterly and drastically different worldviews and priorities. This sort of thing is part of why I moved away from a profoundly hostile city.

We both want affordable housing. I just want it to be legal to build it closer to jobs.

Driving is dangerous, as are its byproducts. More driving kills more people.

If the choice is between cheaper housing with a longer commute, or expensive housing with shorter commute, it's completely unclear that the latter is more beneficial to humanity than the former, even if we only consider the number of deaths caused by each scenario. At the very least you haven't presented any evidence that this is so.

That is not the choice.

When people say that doing X has "negative value", they usually mean that it has negative value compared to not doing X, not compared to some imaginary solution that doesn't exist in reality.