I dont disagree but where does the funding come from? There are many issues around this is schools.
TAs used to offer pastoral support and support with low level behavioural disruptions in class so the teacher could teach. But then more teaching was added to their role running booster groups, interventions and pre-teach sessions. So they now longer do this.
Then the budgets were slashed which means I'm going into my 6th year without any TA support at all even though I have taught many high needs children (behavioural, cognition and learning, and significant pastoral needs) during those years - and have dealt with violent attacks on myself and other children. I don't know of any schoools that have a class based TA outside of KS1 personally.
Teachers could do more if the curriculum weren't so overstuffed you can hear it groaning at the seams.
Less stuffed curriculum, the capacity for a slightly slower pace and the opportunity to consolidate learning would also help. There is a big problem with cognitive overload in children due to the curriculum. Address this, and a lot of the behavioural issues would be reduced.
Last week, I came on during the first lesson of the day. No one else in class and no phone to call the office to ask for someone to come down for 5 mins. My only option was to send the emergency 'red hand' which would have brought the Head Teacher to my door expecting a violent/severe behavioural incident or a severe medical issue/accident in a child. I didn't feel I could do that and tell him I needed the loo so I just had to manage until breaktime an hour later.
I know that last paragraph is an aside but there are many problems in schools.
There just isn't any money.