Let's put it this way. If you can break it and are willing to commit crime - you can earn a lot of money. I'm personally not equipped to judge the level of security, because I'm not a cryptography researcher. What I understand is that the overall ZK cryptography space has been around for a long time, and basic properties are well researched. I tried to read the PLONK paper for entertainment purposes and it's quite easy to understand.
If you want to prove a program, you need to convert it to what is called "arithmetic circuits". This is a clever way of saying "a system of polynomial equations". It is as if you're converting the code to logic gates but instead here you use arithmetic: addition, raising to a certain power, etc. It is a process called "arithmetization".
The proof calculation involves folding this system of equations in various ways and collecting a "witness". Not sure if I'm explaining this correctly, but it's probably in the right direction at least.
The problem with all ZK proofs is that the last bit of calculating the witness is very computationally expensive. What takes milliseconds to run on the CPU can take many hours to prove. And a lot of research is focused on clever mathematical tricks that allow to speed up the proofs while keeping the risks of circuit compromise low enough. As you may guess, the more bleeding edge the research the less it is peer-reviewed.
So I'd say that "it depends".
As for DRM - probably not. At least not in a way that companies installing the DRM would want it to work. They likely want you to be unable to decrypt something at all outside of a particular chip, and watermark the video on top of that to be sure that you're not screen-capturing it.
UPD: there's a decent free into course into modern ZK cryptography: https://zkiap.com/
Proving performance is improving at a rapid pace though, like 10X/year. And converting to circuits is automatic now; there are compilers that can do it for arbitrary Rust code.
If you want to prove a program, you need to convert it to what is called "arithmetic circuits". This is a clever way of saying "a system of polynomial equations". It is as if you're converting the code to logic gates but instead here you use arithmetic: addition, raising to a certain power, etc. It is a process called "arithmetization".
The proof calculation involves folding this system of equations in various ways and collecting a "witness". Not sure if I'm explaining this correctly, but it's probably in the right direction at least.
The problem with all ZK proofs is that the last bit of calculating the witness is very computationally expensive. What takes milliseconds to run on the CPU can take many hours to prove. And a lot of research is focused on clever mathematical tricks that allow to speed up the proofs while keeping the risks of circuit compromise low enough. As you may guess, the more bleeding edge the research the less it is peer-reviewed.
So I'd say that "it depends".
As for DRM - probably not. At least not in a way that companies installing the DRM would want it to work. They likely want you to be unable to decrypt something at all outside of a particular chip, and watermark the video on top of that to be sure that you're not screen-capturing it.
UPD: there's a decent free into course into modern ZK cryptography: https://zkiap.com/