The payments are based on your earnings, so it is a kind of graduate tax - but only up until around retirement when any remaining amounts are cancelled.
In effect, more successful English graduates subsidise everybody else (because it is supposed to be revenue neutral). And specifically English, because only English students pay the full £9,250 per year. (Scottish students pay nothing, Welsh and Northern Irish a reduced amount).
The English subsidise the "United" Kingdom but are discriminated against when it comes to social provision paid out of general taxation. Unlike Scotland, Wales and Northern Ireland we do not have a Parliament for England looking after England's interests. Instead we are ruled by the Union Parliament which includes MPs from Scotland, Wales and Northern Ireland whose remit and interest is their own respective nations, not England, but who get to vote on legislation that affects England without England having the equivalent ability to interfere in the Scottish, Welsh and Northern Irish Parliaments.