So we are now all about progress 8, it's progress that counts and getting a B to an A is as valuable as getting a D to a C (except for slight quibbles about numeric values). This is seen as a good thing, all pupils will get support to reach their targets.
What I'm seeing: There is a limited amount of maths intervention available to help students - 1-1 and small group tuition at tutor times and so on. Previously this was focused on C/D borderline kids to help them get the magic C grade and boost the school headline figures. Now it is given to students who are falling well short of their target grade, who need the double weighted boost of an increase in a maths grade to improve their overall score.
I teach several students who are sitting on a 3, and with extra support could reach a 4 - the key grade where they won't have to resit in sixth form, and which will ensure access to certain college courses. Getting a 4 would be extremely important to them. They are not on the intervention lists, and not getting the help that they would have got in previous years, instead it's going to other, higher (and lower) achieving students. The grade that is important to them is no longer important to the school.
In practice 'more support for all' seems to mean 'less support for those to whom it really matters'.