Works for me. The "Installation" page includes the phrase " (supported shells today are bash, zsh and fish)," for it in the section on the shell function.
going slow definitely should not be dangerous. speeding is dangerous. there is slight difference between city and highway infractructure. almost everyone forget that "speed limit" is not "recommended speed".
lets not stigmatize innocent people, and pursue those, who actually are breaking the law
No, because you can't reasonably ticket people for going only 5mph over. There's a reason almost no cops bother doing so, and set their threshold at 9 or 10 over: car speedometers aren't that accurate, cars can easily vary their speed a few mph as they drive, radar is only so accurate, etc.
And yes, "speed limit" really is "recommended speed", because that's how people drive in the US today. You wishing it were different will not make it so.