Whether fake dating to cover up for someone’s alternative lifestyle or being unable to date freely without denials. The only reasons this is the rule in kpop is not due to privacy or morals, it’s profit.
A small small part of kpop’s success is the actual music. Casual listening wouldn’t generate enough.
The main source of business are the parasocial relationships between fans and the phantoms created by idols. And this is taken to an extreme degree to secure maximum profit. Whether it is creating the illusion that the idol has absolutely no concern for love matters and just cares about their music or having to act like a bf or gf cutout for deeply tranced fans.