DRM is built on a self-contradictory premise that tremendous amounts of effort are going into making work. Namely, if we save content in a special format, then we can make it impossible for it to be used except as we decide.

However they then put that software on hardware controlled by people whose interests are not necessarily aligned with that goal. And once there, that software can be changed. That hardware may be an emulation that can also be changed. And so on and so forth.

To make the fiction appear to work, they need to find every way that they can to avoid escape. They add detection code that tries to identify running under emulation and blocks it. They obfuscate their software in every way that they can. They only place their software in other software that they trust. They embed various checks that nothing looks suspicious.

And even so, they are doomed to fail. See https://krebsonsecurity.com/2020/10/google-mending-another-c... for example. But they just need to make it hard enough to bypass the encryption that it is hard to get pirated copies. And make the penalties for trying to do so to discourage a pirate scene. And this they have done.