Foreign carriers seem to do just fine with judicious use of the seatbelt sign without having an inordinate number of injuries.
Turbulence injuries will never be eliminated, but they are statistically insignificant compared to other sources of risk in people's lives such as driving.
I was a little shocked to see what happens in Europe. People up and switching seats during taxi, up right away after takeoff.
If you get up during taxi in US you'll probably get tackled to the ground