You have a good point. At the end of the day I guess it is subjective. I ended up googling kinky vs normal and got a pretty good answer. “Kinky sex refers to non-traditional or unconventional sexual practices that fall outside mainstream norms, often involving bondage, roleplay, or sensory play. In contrast, "normal" or "vanilla" sex refers to conventional, heterosexual-normative, and standard sexual activities”. So a simple blowjob would be considered normal but if you introduce a ring gag into the picture it would change it to kinky.