The DNC arguing in court that they don't have to abide by primary elections isn't the same thing as the DNC actually not abiding by the primary elections. The DNC absolutely abided by the primary elections in 2016, and there's no evidence to the contrary.
Sure, the superdelegate system was overwhelmingly for Clinton, but Bernie was already behind in the elected delegate total. Either way, in 2018, the DNC changed the rules so superdelegates can't even vote in the first round anymore, so will only get a vote if a convention is contested.