Listen its a dangerous and stupid suggestion. Its Naive, and dependent on others doing the right thing, when they have already started not doing the right thing, BTW a temptation of being in a vehicle, when people are mobbing it is to start it up and run people over, what do you think would have happened then?
Listen, I do not need to ask someone who has tasted a turd what it tastes like to know I do not want to try it. The same follows here.
I am perfectly in my rights of free speech, to express myself in the most direct and honest way I know how. I suggest instead of trying to be politically correct you might try the same.
There are ways to tell someone that you disagree with their ideas. There are ways to tell someone that you disagree with their ideas without belittling them or calling them names. I for one do not mind being told that I'm wrong or that it's in someone's opinion that I have a stupid idea... I DO mind being called a moron and I'm sure others here feel the same way.
If I'm to be told that I'm wrong then I will want to know why.
You certainly are within your rights to free speech here as long as it's respectful and does not trample upon the personal dignity of someone else's intelligence.
The only time that you would be way out of order would be to express; racist, sexist, or any other bigoted commentary along with your statements. Calling others "morons" is a slight upon the intelligence of this (on line) community.
Regarding the act of getting in the relative safety of one's vehicle, particularly in face of being heavily outnumbered and an angry mob at that which is what that actor was faced with, I'll add to your own ideas that he may be tempted to start the car up and run someone over.
If the actor had done that then he'd be certainly guilty of assault with a deadly weapon but if he himself isn't prone to uncontrolled acts of violence, i.e. turning on the car and running people over as you say... then he would know to simply sit in the car, get on the phone to the police and request for help. Any damaged wrought upon the car can be charged to the folks via credible witnesses and likely the video.
I don't become dependent upon others to do the right thing when it comes down to me. I'll take care of myself first and foremost and if that means getting to a place of safety, then by all means I will. If others DO the right thing by me (helping, protecting, defending me when I'm heavily outnumbered) then praise to them for being decent human beings. Just don't get in my way if I need to take matters in my own hands. If I'm seeking an avenue of escape, again get out of my way or provide legitimate assistance.