Actually the beating is more because of endorphins and people having atypical reactions to pain in general. Every once in a while a class on that topic shows up at bdsm events and it’s always a fun one.

Degradation seems to be less about people interpreting it as love, but more as processing trauma or self esteem issues through role play. People don’t want to get spit on by someone who actually detests them, they want to get spit on by someone who pretends to detest them.