I've seen multiple articles on this, but none really explain why the public toilets that are used at other locations in SF cannot be used in this instance. Another comment in this thread mentions Paris's sanisettes, and SF already has a similar product (though far fewer of them). Given the city has already put them several places, I would have thought the marginal bureaucratic effort for one more shouldn't be so large.

https://www.sfpublicworks.org/services/public-toilets