It's becoming increasingly clear that every franchise has it's own vision of leadership and how it should be structured. Look at Denver where Elway recently gave up his GM duties but is still functioning as Team President. When you figure out who's doing what going forward in Denver, let us know - because it's clear as mud!
I don't know what the key factors are with Kyle Smith. There are a lot of possible things that could be going on, to include:
1) Smith already has a future gig elsewhere, it just hasn't been announced yet
2) Smith has no desire to be a 'GM'
3) Smith wants to be a 'GM', but not with the parameters as described in DC
4) Rivera doesn't think Smith is the right guy to be our GM
5) They've offered Smith everything but the moon to be our GM but he has declined
Those are just some examples of possible scenarios. Most fans would react most against #4 - the idea that Rivera may not see Smith as a good GM candidate, either based on his assessment of his talents, or due to 'fit' with the new Head Coach. But my response to that would be - what do we really know that's the basis of arguing the point? Yes - Smith has been the most obvious central figure in a string of pretty successful drafts. By all accounts he is a talented front office guy with a bright future. All that could be true and Rivera still not feel he is the right guy. Unlike we fans, Rivera doesn't worry about our perceived history of always letting the most gifted and bright leave DC to thrive elsewhere. He hasn't been a part of that nor does he care about it.
I'm sort of over it at this point. There's no denying we've drafted very well (setting aside some blown, likely Snyder or Allen-related, picks). That's the result of a top-notch scouting/personnel department, not necessarily all that is required of a GM. As
SilentThreat referenced, the truth is that we don't even know what is in the GM job description at this time, so it's very difficult for fans to determine whether Smith is a good fit or not.
All we can do is wait and see. Not to oversimplify things, but at some level, we either trust that Ron Rivera knows what it is he is doing and will fill key roles with highly competent people - or we don't.