The source paper for both articles is paywalled, so maybe it has a better argument than the articles. But to call it theater or a publicity stunt is to imply it didn't have a point beyond public relations, which isn't the case.

Microbes can't be completely contained - easily, anyway - and we knew that perfectly well back then. But we also knew to minimize contact with potentially infected people. Put it this way: if there were lunar germs that the astronauts took back with them, would it have been better to skip the containment procedures, as inadequate as they may have been? Of course not.

NASA played up their ability to contain extraterrestrial microbes for sure. But the containment procedure itself was the best that could be done. If 'absolute isolation' is the bar to which containment is held, by that logic everything short of just not visiting other celestial bodies is theater.