Some do vary quite a bit, some not very much. Many but all new vehicles have the engine info gauges controlled by the ECU to display" normal "readings unless something is really out of specification.. Engines with electric cooling fans can see a 20 degree temperature swing depending driving conditions as the fans switch on an off.
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If you listen,look and feel, the engine has a lot to say .....However on new stuff it's been muffled ,less is better 
Both the bike and the car have electric fans (one on the bike, two on the car), and both just display oil temps in degrees C, with no indication of what is 'normal'. I suppose both also have idiot lights that will indicate something is amiss, probably after it's too late
I hear the bike fan cycle on and off all the time, in heavy traffic. The displayed oil temp varies by maybe 5C max in either direction.
As I said, it's just idle curiousity to me; I've not had a vehicle overheat for many years, even air/oil-cooled bikes. Last one was due to a blown rad on a Honda Accord, which was made obvious by the giant white cloud behind me, no idiot light req'd. When I replaced it I discovered that it, along with the hoses, had been nicely gnawed by a porcupine. Up here there are areas where people park their vehicles in little wire-fenced compounds for just that reason. I was camping and didn't have that luxury.
And yes, I certainly don't mind the muffled bit. A nice tick from the valves at idle on a bike is all I really need to hear. Both the Guzzi and the Beemer are audible and somewhat reassuring. I'd probably worry if I stopped hearing it
