Boudin and his defenders have been trying to spin the rebuke (including the apology, which was actually to the trial attorney, not Boudin), but the comments are perfectly consistent with this critique of Boudin's office from earlier this year: https://www.marinatimes.com/why-colleagues-say-district-atto...
Boudin famously fired at least 7 veteran prosecutors immediately after taking office. (https://www.kqed.org/news/11795676/why-did-san-franciscos-ne...) I'm not sure how many more prosecutors were fired or left after that, but as far as I can tell 7 is about half of the total number of prosecutors. And he seems to have replaced them with public defenders and fresh law graduates who have no experience prosecuting cases. (Boudin himself had never prosecuted a case.)
Boudin doesn't deserve all the blame. His predecessor, Gascon, made several changes that already made the San Francisco District Attorney's Office one of the most lenient in the country. People compare Boudin to the reformist D.A. in Philadelphia, but the better comparison is Gascon; Boudin took things to a whole new level, far beyond the reforms in Philadelphia or in the national conversation.
I've always been on board with Boudin's push for more lenient sentencing. But that's just a small part of his agenda, much of which simply translates as no sentencing. And because of general incompetence he's flubbing everything, resulting in him becoming defensive, spinning and lying about cases (e.g. most recently--last couple weeks--a controversy about disparate treatment of some pedestrian death cases that resulted in his firing the office's victims' advocate) that really should have seen both better attention by his office and, mistakes notwithstanding, a better defense in the media.