Any acceptable risk level accepts risk which accepts a death rate.
THAT MEANS YOU ACCEPT DEATHS.
It's more complex than that. The key bit here is 'uninvolved third parties'. It is a recognised principle in aviation regulation and safety management that the
acceptable risk associated with third parties is lower than that of involved individuals. If the Shoreham Hunter had ploughed into the crowd line causing a similar number of casualties we probably wouldn't be having much of this discussion. We would have tweaked crowd lines and carried on. Crashing on a public road, killing uninvolved members of the public, opened Pandora's Box.
I do agree that there needs to be an acceptable number and the appetite for no deaths is neither practical nor reasonable; deaths are inevitable. After Shoreham, the UK (in the shape of civil and military regulator) decided that the existing risk level was unacceptable.