Slowing down is a lot safer than plowing into a stationary object at high speed. This is so obvious there must be something missing to the conversation.
Self driving cars are going to be driven a lot, so something that’s a 1/10,000 risk that happens every week to 1 million cars is going to happen every day.
Self driving cars need to have a threshold before hard breaking. Hard breaking is risky, it can cause serious accidents. Reducing that threshold thus increases some risks even if it lowers others.
So, now we need to balance a risk of say ~1/10,000,000 per car per year vs what? I don’t know what changing those thresholds would result in, but I do know it’s not free and there would be false positives.
Everything you wrote is plausible or true, but the fact remains slowing to a stop is the best choice unless the obstruction is tiny. That’s what a human would do. There might be a possibility of changing lanes but that is next level.
False positives are dangerous. Trying to detect ‘Anything’ may result in more deaths than hitting the tiny number of exceptions.
Alternatively, the system would be overly flakey and hard break all the time.