A bit of topic but I noticed the Cessna 172 can be started in a way the real aircraft can’t be started and I believe it doesn’t start using the real world procedure but I’m not 100% sure about this.
The default C172 has an indirect injection engine, meaning that a fuel nozzle continuously sprays fuel behind the intake valve rather than the fuel being directly injected into the cylinder at the right moment. This means that the C172 cannot be started with the mixture full rich! In real life the engine would flood and fuel would poor out of the exhaust in liquid state.
The usual start-up procedure is to open the throttle slightly, turn on the fuel pump, then open the mixture for x amount of seconds, or certain fuel flow on the fuel flow indicator (if installed) is reached. Then mixture idle cut-off, fuel pump off and that is the configuration the engine is started in (mixture cut-off). As soon as the engine fires up, smoothly advance the mixture to full rich.
I’m not 100% sure about the correct C172 start-up procedure but it must look like the above, that is the only way a indirect injection engine can be started without flooding the engine.
Edit: found the C172S start procedure:
Edit: the start-up procedure in MSFS does not make any sense. The C172 can be started with mixture full rich and pump running for minutes, in real life the engine would have been flooded completely. It could also be started with mixture idle cut-off, but you don’t need to prime. You could start without priming any fuel and the engine would start for a few seconds, and again, and again, and again until the battery is flat. Mixture idle cut-off all the time, no fuel in the engine whatsoever.