Now, couple that with: 1) a general approach of "when in doubt, brake" and the hacky workaround to suppress braking if it's occurring too much, and you've got a bad nuisance braking problem that's primed for a safety incident.
But again, this is disjointed from reality. I'd agree that if we all left the recommended 4.5 seconds of stopping distance, we'd all be safer. But that's not how our roads were built and that's not how humans drive. You're tilting at windmills here to make a point that doesn't need to be made because it doesn't apply to reality.
Oh, it emphatically is how our roads were built. Most miles in the states were still laid down in an era where cars didn't do more than 45. As for how humans drive... I'll direct the audience's attention to the 3,700 per day road fatality rate in the United States. Even if they brake check more than human drivers, an automated vehicle being forced to follow its programming to maintain a healthy follow distance may very well save lives, especially in an ecosystem where they are the dominant vehicle on the road as opposed to human operated vehicles.
The Uber fatality from years back showed that the software used "action suppression" to mitigate nuisance braking. The idea that that would be acceptable on a safety-critical software application should give us pause to consider that more automation is the knee-jerk solution.