Of course there are prophets...it's the basis of our economic system.
Okay, poor joke is out of my system; onto the meat-n-'tatos.
My guess is, Christianity objects to the idea of modern-day prophets (MDPs) because, in a nutshell, MDPs are a threat to the religious "profits" 😉 garnered by the Christian Hegemony (I apologize beforehand if my wording is offensive).
As to why there are apparently no MDPs may be because:
1. Actually, there are, but because of the Christian Hegemony on the one hand, AND our secular-scientific paradigm on the other hand, their true nature is not appreciated or made fun of. They can't get the audience they deserve.
2. There are No MDPs because our lives--our heads--are so full of incessant noise (whether it's worrying about one's "investment portfolio," listening to an iPod 25/8, or whatever), the subtler impressions in consciousness which our religious forefathers were able to attune to are just plain drowned out, like the Sun rendering the stars imperceptible in the daytime.