True but gas turbines (not ICEs, those are mainly used on small aircraft) can reach a theoretical efficiency of 30% while electric motor efficiency of 92…93% is quite common. So you can multiply that number by 1/3 since 2/3 becomes heat.
With turbofans and turbojets it gets a little harder as well, since unlike stationary turbine generators, not all "waste heat" is actually wasted, when considering thrust-specific fuel consumption.