"Yet we should use these deep red states to determine who the Democratic nominee should be."
Last time I checked, we claimed to be a national party. If you want to tell Democrats in Texas, Georgia, South Carolina, etc., that they shouldn't have a say in choosing the party's presidential nominee, go right ahead.
You want to add them to the Democrats in Florida and Michigan?
Apples and oranges. Those states didn't ignore the DNC's explicit instructions.