I'm a parent, with SEN child, now home ed, originally from abroad.
I feel for the teachers in this country, the big class sizes, the very long days.
My SEN (now 11) child couldn't cope with class sizes that big, there were no SEN school spaces so we home educate. I don't see how the 'inclusion' can work specially for 'high functioning' autistic kids who need much smaller classes, but mainstream curriculum.
Where I'm from (Eastern Europe) school day is 4 hrs long, so teacher can do prep/marking straight after and then just go home. Class sizes are generally 18 max until 11, then generally 20. Schools are much smaller, secondary will be 300 normally. School is compulsory, so no one can be excluded. Yet bad behaviour or SEN isn't widely known at school/catered for. I think because kids start at 7yo, they are more mature, are able to spend more time playing for longer. I took this approach with my other home ed child (no SEN), who had no interest in learning till quite recently, but was able to pick up several math concepts in an afternoon - we now do more structured learning, surprisingly he learned quite a lot of math via play and whatever he didn't finds easy to fill.
Because of more varied curriculum and also because parents don't really have much interest in day to day school things, kids just get on. There isn't that pressure of reaching x amount of GCSE's, otherwise you are failure. There are different types of school available in secondary, so kids who aren't interested in general learning can pick coding and specialise in that at 14.
I think part of blame needs to be laid at safeguarding and Social Services.
Parents are terrified to let kids do any of the stuff they ought to do at their age, due to possibility of injury and/or being blamed if something happens to them.
For example, kids abroad quite often walk to school at 7. They go off out and play independently of parents.
My nephews are the same age as my kids and they are much more independent. My sister laughs when I say they have to wait till 10 plus to walk to school.
My SEN child was able to drive petrol go cart (can do at 6), go summer Bob sledging and do various other activities, which in UK aren't accessible till much later because of 'risk'.