Yes, superdelegates are important to upholding Democratic party interests because they allow additional individuals to participate in party politics and offer a vote on important issues. Allowing superdelegates the important job of participating makes them feel like they are part of the process and allows them to feel included in the process, which makes for harmony within the party.
No, superdelegates are not important to upholding democratic party interests, because they are nothing more than people considered important to the party exerting extra influence. Some people who control the party have more say than the average voter in who becomes the nominee. This frustrates voters who want to have a fair say in the process.