"You making the millions, you're doing the media."
That's Marcellus Wiley telling TMZ Sports ... Naomi Osaka should NOT get a pass from speaking with reporters after matches -- even if she's claiming it's for mental health reasons.
The former NFL star says the tennis player straight-up just HAS to do the post-match sessions ... explaining the interviews are one of the biggest reasons for the sport's popularity.
"How do they think that this sport is driven?" Wiley said. "Just because people show up and pay for cotton candy?