I think this has the potential to brutally and horribly backfire.
It has been my experience that in some subcommunities of SO, and in some other sites in general, your only hope of getting accepted as a new user is to not act like it. You're expected to know your stuff, you're expected to "seperate"separate yourself from the chaff".
I think there'll be a small but critically large enough contingent of people who have been waiting for this for a long time. We've had calls to implement options to automatically ignore questions from new users for a while, what do you think these people will do with this new information?
Maybe I'm too pessimistic about this, but I have a feeling that the occurenceoccurrence of "first post, instantly downvoted and closed, and completlycompletely shut out" is going to increase with this rather thenthan decrease, at least in some subgroups of stack exchangeStack Exchange.