That is an interesting point, If this had travelled over one of the poles would we have noticed? I tend to think that someone would have seen it, but we wouldn't have a dozen dash cam videos of it.
The infrasound detectors mentioned in the article can supposedly detect a 1-kiloton blast anywhere on earth [1] (page 15). This meteor was "hundreds of kilotons".
It also would show up on satellites that monitor for rocket launches and nuclear explosions. But whether or not the details would be released to the public is not entirely certain.
That's true - we would detect it now. But the CTBTO International Monitoring System is a relatively new development (design and construction didn't start until 1997).
