That's assuming the intention of DPoS is one delegate = one person(or more).
Its not written in stone but thats what we implicitly assume and expect to be. Keep in mind that the network is in bootstrap phase, and right now this gets some leeway.
I think theoretically you could get a pretty reasonable amount of confidence in 101 DPoS delegates if each delegate was forced to provide significant proof about their real identity including live streaming. Tax documents, IDs and such too. I'm someone who supports the right to stay anonymous in general and I don't put a lot of stake in people providing their real name and such. But some really invasive protocol to prevent Sybil attacks seems like it could plausibly work.
Same issue here, that its in its early days. Right now I can name around 20 delegates who are publicly known and have been working diligently for a long time. Over time if it can go to 51 then there is no problem.
I can also foresee that shareholders won't be favourable to anonymous delegates in general. I don't expect 51 anonymous delegates to get voted in, no matter the incentives, over the older, known and trusted delegates.