It's important for metrics to be measurable. Throwing in a bunch of subjective criteria like how tricky a road is will only make the analysis less meaningful.
Yes, it's important to understand the limitations of the metrics, but the existence of limitations doesn't mean that the metrics should be thrown out entirely.
Measuring metrics that are easy to measure doesn't help if the metric doesn't mean anything.
Comparing collision rates between human drivers in all conditions and Tesla automation in conditions where it allows activation and is activated is simply not a usable comparison.
Certainly, there's not an easy way to measure the collision rate for all humans all cars in only the conditions where Tesla automation can be activated, and that makes it hard to find a metric we can use, but that doesn't mean we have to accept an unusable metric that's easy to measure.
But if you are like Tesla and can not even be bothered to put in a methodology section... or any analysis... or any data... really anything other than a soundbite conclusion then maybe you should not get a free pass on driving vehicles when you only demonstrate a level of safety analysis unfit for even a grade school science fair.
Yes, it's important to understand the limitations of the metrics, but the existence of limitations doesn't mean that the metrics should be thrown out entirely.