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Prior to around 1980, cars and trucks had large radiators and very free airflow through them, and engines ran fairly cool. Even the standard thermostats were 180°F, again permitting cool engine operation, with the intention of enabling long engine life. When fuel efficiency and air pollution came to be politically important, the advantages described above, of intentionally reducing the effectiveness of the cooling system to reduce the cylinder heat losses to increase efficiency, started appearing. Now, nearly all vehicles have rather small radiators and they have small grilles allowing air in to them! Modern radiators are actually too small to avoid overheating and so cooling fans are necessary to keep engines from boiling over. Similarly, modern thermostats are generally 195°F, which raises all the engine temperatures by 15°F. Look in any engine compartment today and you see a clutter of things surrounding the engine. That was not the case long ago, when free air flow around an engine was desired for engine durability. Now, the highest possible engine operating temperature is used, (reduced cooling performace described above) to improve engine efficiency and performance, which also reduces the amount of air pollution created in the process. Engine durability is less than it used to be, but people rarely seem to keep vehicles as long as they used to, so it is apparently not considered a problem.
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Something to think about. Keep in mind the number of people that lease BMWs (as opposed to Honda, Toyota, etc.).