I know what you're saying, but that is not what I'd meant. Also, I don't follow too closely.
The difference here is that almost always a driver will brake depending on the happenings in front of them. So, if you pay attention to not only the car in front, but in front of them and in the neighboring lanes and so on, you can sense and also detect patterns in how a particular driver is driving. There are many skittish drivers who brake every 1 second and some don't, and so on. Basically based on your driving experience you can predict a little.
The problem here is that this stupid POC FSD will brake randomly or change lane randomly or whatever, so there is no way you can predict, and hence my concern and issue with it. I just prefer to change the lane, but that's not always an option.
Yes, we all do that AND you're using that predictability to take liberties in safety such as following too closely. FSD's unpredictability exposes the vulnerability in your driving process and makes you feel uneasy.
You (and everyone else) can follow too closely AND FSD can be an unsafe steaming pile of crap. It's not an either or situation.
Irrespective of the Teslas or FSD:
If you're afraid of an accident due to the vehicle in front of you braking regardless of the circumstances, then you're following too closely. It doesn't matter if the braking event is anticipated or unexpected. If you're not confident in your ability to avoid an accident if the vehicle in front of you slams on their brakes then you are following to closely.