Not only is the belt
not his most powerful marketing asset, its quite literally meaningless to his market value.
I actually have to laugh at the idea that the belt has any meaning whatsoever relative to Conor's selling power. It's truly 100% inconsequential.
I also have to laugh at the idea that he has ever ducked Khabib when beat Alvarez for the title, fought Floyd Mayweather and has now signed to fight Khabib. Where's the duck??
I'm genuinely confused by your logic. His first fight signed after Mayweather is Khabib and you say he's ducked Khabib?
...
His entire rise was based on belts. If it wasn't for them he'd be a hardcore favorite only. There's a reason casuals made him a superstar, and a reason it didn't happen until belts were involved.
Q: When did Conor hit it big?
A: Either winning interim BELT or FW BELT
Q: When did Conor become a superstar?
A: Becoming the owner of TWO BELTS
Q: Why did Mayweather fight him?
A: Once he was the owner of two BELTS/not the "random Irish guy from the UFC."
Q: What is the most common promo image of him in UFC history?
A: Holding two BELTS
Q: Why did WME allow him to set the record the longest non-defense in the history of MMA?
A: Because they wanted him to maintain his BELT (aka marketability)
Q: How is this fight being marketed?
A: Conor coming back to get a BELT
Again... the duck was 223. And 222. And 221. And 220. And every card that WME would have LOVED to book him and he didn't. They pushed Khabib (and Tony) vs Conor over and over and he refused over and over, up to and including the night he lost his belt due to refusing to fight Khabib. And the best part is no one has a single excuse why he set that record for non-defense. Other than "he is rich" apparently ha.