I think we have it all backwards as a society. School is such a powerful concept. I'll admit I'm biased because I have 3 children who were all broken by their schools, and I had a really hard school experience myself (but didn't know you could be broken, so hobbled through), despite being extremely intelligent. I'll try to explain but I haven't got it crystallised in my mind yet.
This whole thread is about 'school readiness', as if 'school' is a defined thing. However, I've been a governor of primary and secondary special schools, and infant mainstream schools. I remember sitting with my Head Teacher as they motioned to huge folders that lined the walls, saying 'all our work for the last two years has been scrapped', because the Government changed their mind on what the curriculum should be. I remember sitting in an Ofsted inspection, being told that our school would be graded inadequate for teaching and learning, because all of our children had SEN, so couldn't have made good progress. The fact that my daughter had gone from 1:1 support at preschool, to being able to leave her classroom with the register, walk to reception, and return to the classroom without running away, was irrelevant.
The Frameworks changed 5 times while I was a Governor. Curriculum changes, changes of expectation. Ever focusing on theoretical knowledge rather than life application.
When my mother was at school, they had dining rooms and kitchens and household skills were taught. When I was at school, we had a Noah's ark in the corner of the classroom and we spent a whole term painting it (shoulder girdle muscles are important for handwriting skills) and we did projects on survival which incorporated writing and geography and science, and extended writing projects. Now it's split digraphs, etc.We had regular music lessons, all as a class.
School shouldn't be the main factor in a child's life. We shouldn't be worrying about being 'ready for school.' School should a part of being 'ready for life'. That's what's wrong.
DD1's school experience declined in year 7 when she was allocated the wrong type of special school. They had misjudged her ability and placed her too high. She needed the all round experience of a Learning Disability school, but was placed in a Moderate Learning Disability school, which is more akin to 'slow mainstream'. It destroyed her, she was hospitalised, and she is still in mental health crisis at 20.
DDs 2&3 also had terrible experiences in what would probably be regarded as a 'good school', for different reasons. One was ignored when she floundered. The other was badly bullied and got very ill as a result. I was still getting 'Oxbridge potential' emails 7 months after she had last been able to attend. They'd forgotten to take her off the list. Both girls are in special schools for kids with EBSD now.
My point is that schools aren't meeting the needs of society. It isn't the teachers' fault. It is the fault of the governments. The wrong focus has been set and a large proportion of children are failed. A system where, by design, 40% of children fail to leave with the qualifications that allow them to progress to the next stage of education is barmy.