I do wish that the article would have explored what, if any, danger there is regarding possible restrictions. Is that a legitimate threat? That would be useful information to include because it would allow readers to weigh the urgency.

This isn't an issue of referendum vs. legislation. It is an issue of timing and resources (well, at least according to Planned Parenthood, the ACLU, and Democratic leadership).

The article explains that initiating a referendum would have been difficult and not guarenteed due to Republican opposition.

That leaves going the legislation route, which would come with complications (timing, resources). It's not like they can just gather and vote today and it would be done. It's an intensive process that needs to be done right.

On top of that, the article also cites the more pressing need for access vs. passing this legislation. In other words, having a right is useless if access is restricted (similar to voter disenfranchisement in states that aggressively restrict access to voting).