10 years ago it was belt or nothing, now it seems no one cares about belts anymore because people know who the best are. And if there is a belt involved it's icing on the cake. Which is a good thing and a sad thing. It's sad that all the organizations are so corrupt no one cares about them. But good that you don't have to have one to be seen as the best.
Basically no, I often forget when I sit down to watch a big fight that there is a belt involved at all. For the minor title fights where they are fighting for the Interim Silver WBA Challanger belt I certainly don't care an ounce...
Real boxing fans understand that belts are shit without a good fighter defending them. "Title fight" will always score bigger on the marquee than non title fights with the exact same fighters. But in terms of relevance, nobody worries about belts. It's about the best fighting the best.