For all these reasons it seems like kind of a non-starter.
But let me put a counter-argument out there. It's not necessarily an argument for Dean. But it's an argument for what is necessary for Democrats. Dean did not invent but mobilized and embraced the "50 state strategy" during his tenure at the DNC. The Democrats comeback in 2006 and 2008 was based heavily on a rebound in red states. The key to that 50 state strategy was building organizational capacity in every state in the country, even states that seemed hopeless for Democrats. I can't say precisely how much the 50 state strategy helped build the 2006 and 2008 result. I also don't know how much of it was driven by Dean as opposed to him embracing and being the face of a strategy that was mainly driven and implemented by others. My impression at the time was that he had a fair amount to do with it. It's so long ago now I'm not sure how well I knew that or not.
I say this not as support for Dean but more a suggestion that his candidacy not be dismissed out of hand, even as it seems most Democrats are starting to line up behind Ellison. I also think Dean has some point that it's good to have someone in charge of the DNC who has that as their exclusive job (though again, there's ample precedent for a Rep or Governor holding the job.) What I think is very clear and necessary is resuscitating some version of the Dems 2005-09-era 50 state strategy.
Clinton won the popular vote by a significant margin. In all the needed and sobering reflection about what went wrong and why we shouldn't ignore the significance of that - not simply as a gauge of public opinion today but as a guide for the future. But we live in a federal republic. Democrats dominate the culturally dynamic and economically vital cities. But that leaves their voters concentrated in tight geographical areas rather than spread out evenly over the country. That's a particular problem in the House of Representatives - in many ways just as much as the 2010 gerrymander - but it's a basic structural problem at the presidential and senate levels too. Whether or not that's fair or right is irrelevant. It's not going to change, certainly not while the government is under the control of the Republican party whose rule it helps perpetuate.
As I've been writing my Trump mini-book - which has now been significantly delayed for obvious reasons, a point I'll get to in another post - one of the issues I've been grappling with is the politics of demography. As I write in the first pages (no idea whether this precise sentence will survive new drafts and revisions) "in politics, demography is opportunity, not destiny." It requires a politics to give it direction and organization to allow it to act. We are living in a national politics where a fundamental, perhaps the fundamental divide is one between cities and rural areas and exurbs. Right now Democrats have a severe organizational deficit in those rural areas and exurbs. They probably have a more general deficit too. But that's where it's most keenly felt. Democrats need an organizational strategy and politics which is designed to compete in every part of the country.