Properly maintained aero engines start just fine with the correct technique. I've had plenty of car engines that were mongrels to start.
Car engines *don't* have the same shock cooling issues - they're liquid cooled with a thermostat to control coolant flow into the engine so that the temperature is relatively constant.
Car engines don't operate at full power (or some high percentage of full power) then 55%-75% for hours on end. Car engines rarely see full power, let alone operate continuously above 55%. My car specifies 3000miles between changes. Conservatively choosing 30mph average speed (and for easy calculation) that's 100 hrs of use - and not even above 50% power for any of it.