The story buries the lede: there were 19 candidates on the ballot for mayor and 16-30 for each city council district. Several of the experts cited speculate that the number of candidates overwhelmed voters.
I always go over a sample ballot in advance and research each candidate. I would not have liked to do so for that election; local elections are difficult to research in general with many candidates getting minimal press and some not even bothering to put up websites.
I’d rather parties have no official role so we’re actually voting for people to represent us. Candidates have a responsibility to get their message out, and voters have a responsibility to do some research.