After a malfunction like this, a car without a mechanical e-brake can be left in two states, both dangerous -- free rolling or locked in place. You can always

After a malfunction like this, a car without a mechanical e-brake can be left in two states, both dangerous -- free rolling or locked in place. You can always secure a manual car or a car with a parking pawl by shifting into gear or P, so I assume it's more okay to leave them in the free-rolling state if they die completely. But you can't do the same in a Tesla which doesn't have a parking pawl, so I assume someone made the decision that a forever-locked-up Tesla is safer than a forever-free-rolling Tesla. I also agree that should be an even-more-emergency mechanism (like a valve on the brake circuit) you could operate manually to disable the emergency lock-up, but in the case of a Tesla fiddling with that hypothetical valve would also disable your brakes completely sooo. Dunno. The car just doesn't have enough hardware.