I think it will be starting to get better - just.
If you compare us to Europe, we have one of the most regularly tested systems, yet this doesn't correlate to improved outcomes. Our politicians (of all colours) have yet to get their heads around this it seems, but the current incumbents have started down the road of 'regular testing can be introduced as a system of checks and balances for introducing private funding in lieu of state funding.'
It won't work overall - as history and contemporaneous examples in other countries have demonstrated, although there will undoubtedly be some success stories. Eventually, as we suffer a skills shortage, educational attainment doesn't live up to expectation, social mobility remains static (or even decreases), and various think tanks produce their reports, there will be return to greater state control.
Some people seem to believe that private/state control only works one way (i.e. sell it off and never regain control), but if you look at the evolution of state-funded education in this country from the 19th century onwards, plus the introduction of the welfare state, that isn't the case at all. However, what it does require is massive political will (most of our current politicians - in all parties - are far too career-minded than passionate about something they genuinely believe in) and a far-from-passive electorate.
We're not there yet. We've yet to hit the bottom, the politicians don't care, and sadly it seems most of the electorate don't care enough to translate feelings into action. But that won't always be the case IMO. Again, history has shown us that equitable societies fare better and non-equitable societies eventually tend to implode when things get bad enough, and that's when things change.