I have not been in a Tesla with Full Self Drive (FSD) and I was hoping someone here can confirm/deny my theory. The theory is that there will be this dangerous

I have not been in a Tesla with Full Self Drive (FSD) and I was hoping someone here can confirm/deny my theory. The theory is that there will be this dangerous trough with the FSD feature. So at the no FSD end of the speactrum the driver is engaged mentally trying to safely get to were they want to go. At the other end of the spectrum, with fully working FSD that is better than people can drive you are are by definition safer. But! In the middle you have this dangerous middle ground. Its dangerous because the car is doing say 85% of the work, but, you need to be eagle eyed to grab the wheel and/or hit the brakes when the FSD falls into the 15% not working part. The fact that the car is doing most of the work is going to lead to people being bored and spacing out and not being ready to hit the brakes. For example: https://www.youtube.com/watch?v=Ki9RK_JDtIg https://www.youtube.com/watch?v=Ki9RK_JDtIg. To anyone who has spent time in a FSD car, is that the case? Or is it sufficiently fear inducing that you pay super attention?