The entertainment industry calls DRM “security” software, because it makes them secure from their customers. Security is not a matter of abstract absolutes, it requires a context. You can’t be “secure,” generally — you can only be secure from some risk. For example, having food makes you secure from hunger, but puts you at risk from obesity-related illness.
DRM is designed on the presumption that users don’t want it, and if they could turn it off, they would. You only need DRM to stop users from doing things they’re trying to do and want to do. If the thing the DRM restricts is something no one wants to do anyway, you don’t need the DRM. You don’t need a lock on a door that no one ever wants to open.
DRM assumes that the computer’s owner is its adversary.