Honestly, I'm pragmatic, if less people die in accidents involving autonomous car, then yes.
The thing is we shouldn't be trusting the manufacturers for these stats. It has to be reported by a government agency or something.
Similarly Autonomous car software should have to be certified by an independent organization before being deployed. Same thing for updates to the software. Otherwise we would get deadly updates from time to time.
If we deploy and handle autonomous car with the same safety approach as in aviation I'm sure this transition can be done fairly safely.
Honestly slowing down too much can easily create an accident that didn't exist in the first place.
Not every situation can be handled by slowing down.
If that's the default behavior on high speed road this could be deadly for the car behind you.