Still, sex is a generic term… it doesn’t prove that GUYS are doing it as you mentioned in your initial post, nor does it prove that search is being done for pleasure purposes.
If you have not seen porn and you don’t know what it is, how can you ask question about its validity? Why does the man feel he needs to look at porn? Maybe there is something wrong with the woman? Maybe he does not find her attractive anymore? Maybe she doesn’t stay clean, smells, doesn’t shave often, has other bodily deformities, obese, etc. …there could be many reasons…