I think it really depends on the type of relationship/dynamic. To me there's a huge difference between an accessory, a play collar, and a collar that has been carefully chosen and gifted to signify a bond between two people. I have no desire to be collared, but I have no trouble wearing a play collar, and the collar I wear daily is more than just a piece of jewellery to me. And I don't think I would want to collar someone else either, but I might consider it if it's very important to them.
This was a huge topic of discussion in some of the kink communities I was in 10+ years ago, but it always seemed unfair to judge people based on whether or not the collar they wore was gifted by a D. I'm glad that doesn't seem to happen as much anymore.