I mean... it's context to make it relevant to US readers. You didn't see me say there was a direct comparison to be made.
And you're kind of contradicting your claim that it's totally useless. 121/million vs. 1/million shows at what order of magnitude the comparison takes place, which is good enough to contextualize things, and your example of Austin further shows that the order of magnitude isn't far off.
No. We have no knowledge of your neighborhood, whereas US readers have a good-enough picture of the US.
It's also useless because a neighborhood is too small a unit of measurement to be useful, period. Unlike cities, states, or the entire country, the vast majority of neighborhoods have zero vehicle fatalities.
And you're kind of contradicting your claim that it's totally useless. 121/million vs. 1/million shows at what order of magnitude the comparison takes place, which is good enough to contextualize things, and your example of Austin further shows that the order of magnitude isn't far off.