No one in national parties like them but states won’t be told what to do. It’s totally on them. Really it’s the same thing as having an open primary, semi open or a closed primary. It is at the discretion of the state party.
The only way the DNC can compel Iowa to change is to basically get all the other state Democratic Parties to gang up on it and threaten sanctions (such as docking delegate numbers) if they break the consensus. This is actually why Iowa and Hew Hampshire are back in February after drifting closer and closer to January 1st for years and other stares threatening to leapfrog both of them. The DNC since 2016 stepped in to bring about some schedule sanity.
Did fundamentally people have to choose: what do they want, a DNC that can mandate necessary changes unilaterally or a weak DNC that can’t control the process and has to accept an outcome that might go against the party’s national chances. It can’t be both.