This keeps coming up in most countries every few years. Everyone seems to forget in nearly every country telecoms are licensed industries and providing legal intercept is a legal obligation of those licenses.
Based on the responses here can tell this is the crowd who like to recite CS101 algorithms on a whiteboard in interviews.
This approach is overall fairer to students by looking at the whole school year not one three hour exam based. UK exam setup has not really changed in 30 years plus and just because you did it is not a good reason to rethink how this works.
One of the things missed here also is a lot of exam boards historically let the teacher decide if the student is “not great” to sit the lower tier exam and cap there grade to a C no matter if you got 60 or 100% on the exam.