I never sit by when stuff like this begins to happen, I disengage immediately and then my #1 priority is to do whatever it takes for the other (wronged) driver to be able to relax. Sometimes that means gunning it to get away, other times just ceasing all turns and lane changes and being stable at a reasonable speed.
All of this only when possible, of course. But I can only handle 2 or 3 cases where FSD (can we just agree that FSD means FSD(S) by default and could mean something else next year?) really embarrasses me before I become too gun-shy to keep testing that version. So because I enjoy testing, I work really hard to never get into a situation where another driver thinks I'm a total a$$hole. A bit of one, OK, you can't help what FSD does before you manage to disengage, but the last thing I give a hoot about when something like that happens is facilitating the evolution of FSD.
At this stage of the evolution of autonomous driving, I think it would have been doing a service to everyone (and especially we who are in the trenches risking life, limb and rims for the cause) for there to have always been an indicator light or something on the car to indicate the car is at the controls. When I read that Mercedes was forced to do it due to their feeble L3 support, I thought "That's really useful in a lot of ways."
I saw lots of cases of poor timing, but also lots more of good or excellent timing, so hopefully more scenarios will migrate toward the good end of that spectrum.