From my experience (automotive electronic engineer), the choice of microcontrollers for automotive application depends on the application.

If this is for powertain application, microcontrollers must be safe, proven, automotive qualified and highly used by manufacturers.
Some beloved chips are Siemens (infineon) C16x 16-bits familly (C167 is very common). Motorola is also well represented with HC08/05 familly. 32 bits CPU are still not popular for powertrain
The automotive qualification (AEC-Q100 for instance) is required due for reliability purpose. Most of the time these chips are qualified from -40°C to +125°C (you will perform the Fahrenheit conversion) because the ECUs are located in the engine area or on the chassis.

On others Electronic Control Units located in cab, you can see other manufacturers. Tempratures required are lower. I've ever seen Hitachi H8 on dash cluster, ARM ARM7TDMI on main vehicle control, Motorola 68HC08 on Alarm and keyfob, Texas TMS320 (DSP), ...
32 bits are becoming very popular for multimedia applications but not only. As communications busses are also increasing, this requires many protocol ports very difficult to find and manage on small 8 or 16-bits. Memory size is also an argument.

I've never seen 8051 derivative but it doesn't mean it's not used.
Note that today, many chip manufacturers are embedding automotive peripherals (LIN, J1850 protocol, stand-alone chips, ...). Philips 8051's are mainly used in industrial application I guess for the moment mainly because they don't have such peripherals and are not automotive qualified.
So extra components would be required, and you know in automotive market, you try to reduce any cent of dollar the cost of a product.

Here is my point of view, not the universal truth....

Regards
Stephane