DA's have a budget and a limited number of assistant attorneys. They have to manage their office's caseload, and keep cases they do pursue moving through the pipeline. Even then, they must compete with the priorities of the judiciary and individual judges to reduce their caseload and keep cases moving.

It was not uncommon for judges to periodically advise prosecutors, public defenders and other key defense attorneys to convene a forum for the expeditious resolution of cases (essentially a fire sale with lots of bartering) to lessen their load and improve their KPIs.

So I think it is fair to say, Chesa Boudin, in his capacity as managing attorney responsible for setting his office's prosecutorial discretion policy, refused to prosecute the case. No different from any other prosecutorial discretion decisions made by countless prosecutors around the country daily.