Like many discussions here on the board, comments, opinions and "what I have done" may be somewhat enlightening, but in specific tech areas and giving advise like here, it should be based upon some facts and real-world data?
Since the factory GN's had to meet emission standards, there are many items we do not need or use on our cars, but the original underhood temps of a stock GN was at the acceptable limit for normal driving conditions.
When we increase HP, this generates even more heat, but we also compensate by better cooling and other items.
The concern should be oil temperature which needs to be in an acceptable range, not too cold or too hot.
A "garage queen" GN that is occasionally driven will live just fine with or w/o an oil cooler, but in other situations, the needs and results are different.
A modified GN may have a larger oil filter, oil pan, radiator, different fans and other items affecting underhood and oil temps.
In a race car, especially when it is trailered, it is necessary to have the oil at operating temp before it is run at max HP, and that is easy to verify with an oil temp gauge.
When using e-85, the engine will run much cooler than gas, and it will take much longer to reach operating temp. I prefer to NOT use the oil cooler on my street e-85 car as it also has a deep pan holding more oil and a massive fan/alum radiator combination
At the track, I have seen more engine damage from oil being too cold, rather than too hot.
The decision to run a stock cooler or not should be based upon the individual GN depending on use and mods to the car, but this is only my opinion!