"Security theatre" means doing complicated things which are claimed to increase security but don't do that.
The classic example is making everyone at US airports take off their shoes, have their shoes x-rayed, and then putting them back on -- for decades after the single incident in which a man failed to blow up a plane with explosives in his shoes. https://en.wikipedia.org/wiki/Richard_Reid
Moving code out into an optional plugin -- so that it can be verified not to be in use or even removed -- is not theatre.
The classic example is making everyone at US airports take off their shoes, have their shoes x-rayed, and then putting them back on -- for decades after the single incident in which a man failed to blow up a plane with explosives in his shoes. https://en.wikipedia.org/wiki/Richard_Reid
Moving code out into an optional plugin -- so that it can be verified not to be in use or even removed -- is not theatre.