There are many very good points in your post Vince. I would just point out that, in my experience, most teachers would react very positively to a curriculum that embraced wider skills - whatever that would look like. However, teacher's lack of knowledge (or not) of the wider world has very little indeed to do with what they teach. In this country we have an education system that is constructed to (pretty much) only teach knowledge that is (in theory) measurable. Successive governments over the last 30 years have been obsessed with it. Children's knowledge is formally measured at the ages of 10/11 and 15/16. But the crunch is that for many years OFSTED, which in theory operates independently of the government, has inspected schools and made judgements upon them based very much on the results children achieve in those formal tests. Poor test results are published in league tables, might result in an early OFSTED visit, or a poor OFSTED assessment and ultimately the Headteacher being moved on/losing their job. As you can imagine, that places an enormous focus on what a school actually does and has produced a culture in which the emphasis is very much on the teaching of 'traditional' subjects, tests and their results.
Interestingly, in the last couple of years OFSTED, under whats-her-name Spelman, has shown more flexibility and placed more of a 'holistic' approach on judging a school's performance.
In order to create the kind of education system you discussed though, there would need to be a fundamental shift in government thinking as ultimately they are the ones that decide the content of teaching.