Worth taking a step back from the specific exam fiasco this year and look at why we put so much emphasis on high-stakes exams in the English system (not uniquely but unusually internationally).

It's not because we have a fetish for exams but because our university system is incredibly selective. Far more so than in most countries. As we've seen from news clips this week decisions re: specific universities are incredibly important to life chances.

Once you have a system that selective it makes the technical reliability of assessment very important because you want to be as accurate as possible in making those judgements.

Coursework, controlled assessment, teacher assessment are simply not very reliable.

I mean reliable in the technical sense of being able to get consistent grading over the whole system. Coursework etc may tell your more about other things you want to assess than an exam can but that doesn't make it reliable.

All this means we have a much greater focus on reliability of assessment than most education systems and it also means that when exams go wrong (or can't be sat) it causes far more problems because we're not using other forms of assessment.

You can't really change the way we do assessment without changing the way we do admissions for highly selective tertiary courses (academic and vocational) because it would be unfair. The only way to change things would be to make the courses less selective.

People like @soniasodha have put forward interesting arguments for doing this. It would have profound implications for how we organise society (esp the elite). https://www.theguardian.com/commentisfree/2017/aug/17/britain-universities-comprehensives-academic-selection

That said having non-selective tertiary education causes it's own problems which is why Macron has been trying to reform French universities https://www.economist.com/leaders/2018/05/05/france-where-the-grossly-unprepared-try-for-maths-degrees

Also worth saying that we've created a society where nearly all high-status jobs require a degree which again puts more pressure on the education system than is necessary while creating a sharp divide between grads and non-grads. That's a whole other discussion....