SATs are very different to the tests and exams I did at school.
For a start, the pressure on children now is immense. SATs pressure on my son (now home ed and yr 7 equivalent) started in year 5, straight after SATs were finished for the year above.
It was explained to me by his teacher that it was impossible to simply teach well throughout the year, because there were so many specifics that wouldn't be included in a normal year 6 education, and because how well (or not) the cohort perform then reflects on the teacher's wage, so the pressure is not only on the children but on the teachers as well.
SATs represented the beginning of some sort of breakdown for my son. We asked for him to be withdrawn from SATs due to autism and high anxiety levels, the HT refused, in a "well he lives in the real world, he just has to get on with it" way. He opened his SATs papers and was too anxious to complete any. He failed spectacularly and couldn't work independently from that point.
The U.K. isn't exactly topping global charts for school performance. There's been a lot of info out there recently about schooling in Finland, where they have very little homework and no tests until the pupils are older, and a focus on child led learning and children being happy, rather than all this mental-health-problem inducing pressure which is producing lots of unhappy children who aren't reaching their potentials.
I hope more teachers follow suit. Education shouldn't be in the hands of the government at all, particularly not one focused on elitism and results above children's health.