That's a fair point, but I find 7 more dangerous because it pisses off everyone around and thus can cause unwanted and unsafe rage reactions. I always drive on 2 (just because there isn't 1 anymore) and find myself often accelerating manually to cover gaps, based on my own assessment of the driving conditions. I would go 3 only on rainy days, but not more.
Just consider that these safety distance factors already comprise both the inattention threshold and the calculated stop distance based on the current conditions, and are updated an incredible amount of times... every few milliseconds.
Given the continuous increase of automation, which will only make us drivers less attentive and more complacent, I encourage everyone to attend safety driving courses to be able to react in proper ways, and now that's even more important, especially because of FSD.
Having driving licenses doesn't make us good drivers automatically, and there are still schools out there teaching grandpa's hands position 10:10 instead of 9:15, surprisingly, or not to cross hands in a turn, which nowadays is just stupid.
Often the most logical way to avoid a deadly accident is counter-intuitive (such as "don't brake and even accelerate if you spin", or "turn less to turn more"), which can only be understood by... trying it on your own skin.
Which is why I wanted to try how regen braking affects safety in a spin, for instance, i.e. how my car in general behaves upon detecting significant yawing, and I will bring it in a month or so to a safety driving facility for this very purpose, where the car is put in a spin by a lateral-moving platform on a resin pavement to triple the loss of adherence and simulate recovery at much lower speed.
In aviation we train mostly for emergencies, it is appalling how this has never been compulsory for driving cars.
