Based on my own assessments and what I've learned on this forum, I figure the act sex itself basically consists of three main parts; skin-to-skin contact with another person, fluid release and orgasm, a feeling domination or submission. The "validation" aspect happens before sex.
A prostitute can't give validation or satisfy the feeling of dominance men seen to need, but they can satisfy orgasm and the need for skin contact. Since I have low self-esteem from inceldom, I don't think I could "mentally dominate" a woman anyway.