I agree with Yaas . In English Language you are taught to write for your purpose and intended audience. Your intended audience here is readers of a site that expects good quality written English from anyone who is actually capable.
If your purpose is to show that anyone who works hard enough can achieve high GCSE grades, then you are sabotaging your own efforts by your writing style. Either you are showing yourself to be untruthful, as your writing style would not be capable of achieving high grades, or you are showing yourself as unable to write to the intended audience.
I also think you are not comprehending the counter arguments. No one is telling our children that their grades do not matter. Rather the contrary, which is why so many of them try so hard to reach the 4 grade, so they at least achieve the pass that does open doors for them.
I repeat again for the hard of understanding. For many pupils, reaching grade 4 is a real achievement for them, and something they have to work extremely hard to obtain. That grade might not achieve plaudits in the outside world, but their families know how hard won they are, and what an achievement they are for that particular young person, and they are definitely a cause for celebration.