He never said he doesn't know who she is. He said "I don't know what she does" and probably meant he doesn't know what she would contribute to a duet. And like the writer wrote, it is a good point. What exactly would Britney contribute to a duet with him?
I highly doubt he's "pressed" because he hasn't outsold Britney. He's a respected legend, the same can't be said for Britney.
Respect and awards don't mean anything to me. I'm just here for my fave doing great music. Plus, Britney doesn't need awards to be considered a legend.