alt Hacker NewsI suspect that highway miles heavily skew this statistic. There's naturally far fewer pedestrians on highways (lower numerator), people travel longer distances on highways (higher denominator), and Waymo vehicles didn't drive on highways until recently. If you look only at non-highway miles, you'll get a much more accurate comparison.
Then you or Waymo can meet the burden of proof and present that more precise and better information. There is little reason to assume against safety at this point in time except as a intellectual exercise for how more accurate information could be found.
Until then, it is only prudent to defer snap judgements, but increase caution, insist on rigor and transparency, and demand more accurate information.