OK, here we go...
Truth and Fact are different things.
What is a truth for one person, may not be for another.
Relating to penis size: (paraphrased from the movie "The Witches of Eastwick") - Lady A says "I prefer a large penis to a small penis"; Person B says "I've experienced a large penis and I prefer smaller"; Lady C says "As long as it works, it's fine".
All three persons are stating truth as they see / experience it. In this way truth can be subjective.
Facts are different. If a penis is accurately measured at 4", it is, by statistical averages, below average or small. Conversely if it is measured at 7", it is above average or large.
Applying the previous example, Lady A would prefer the 7", Lady B would prefer the 4" and Lady C would be fine with either. Again, each one representing the truth as they see it.
If a person is honest about what they prefer, then they are promoting size realism. If they are dishonest, for whatever reason, then they are not promoting it.
Sexuality is such a vast topic, that it is impossible to group everything together and say something is true. The only undeniable truth regarding sexuality is that everybody is different.
To me, size realism would be being realistic about size. If someone were to say "I've been with 10 guys and 8 of them were over 8" one was 7" and one was 6".", what is the most realistic scenario. Based on averages, the person is overestimating the sizes of the individuals with whom they had experience. Is it possible, yes. Is it probable, that's another subject.
If you are looking for size realism, you can scour all of the print and video to find enough "facts" to fit your idea of what people would prefer. But then you are simply applying a specific subset of data to a generalized population.
Anyone who says what they believe, be it regarding penis size or anything else, is being honest and truthful.
In summation:
1. Truth is individual to each person's experience.
2. Verifiable facts are not subjective and are therefore indisputable.
3. Sexuality is specific to each person and no amount of generalization will make something a fact.
4. Sex should be experienced and enjoyed by each individual in their own way. As long as they are honest about what they are looking for.
Now, if you are trying to find this truth in porn, you are already lost. The porn industry has, for decades, been manipulating and skewing numbers to make people believe that larger penises are preferred. This has bled over into all media, especially in advertising. Advertising takes people's insecurities and twists them to suit its own desires.
That is how I see size realism.
Now, if you are trying to twist this into a small vs large debate and saying that one is better than the other, then you are not promoting size realism, but rather your own individual truth. But I'm giving you the benefit of the doubt.
