Sure, but what else can be done and where is the evidence it will have the intended effect with no unintended consequences? So far we have seen three things: changing racially discriminatory legislation, throwing money at problems (including redirecting government income), and lip service. Is the gap getting any closer?
There's always unintended ( or intended but hey f**k it ) consequences to policy decisions, so I aint even going to begin to attempt to address a bar set so high it literally is never met, let alone one I don't think anyone with any idea would think a practical measure or test. There's always winners and losers when it comes to the allocation of any resource.
But is the gap getting any closer? Well it depends on where you start measuring, and what you're measuring, if you're referring to the Closing the Gap report / initiative, then yeah, there's evidence there that the gap is getting closer, albeit not at the rate targeted. It's easy to mistake failure to meet targets ( as is often pointed out to be the case ) for failure to make progress, ( which is rarely acknowledged ) but of course these are not the same thing.
All that aside, any failure or indeed success of policy is only evidence of the level of effectiveness of that particular policy, it's not evidence that any or all policy will bear the same result. Governments will sometimes achieve stuff, sometimes they'll make a clusterf**k of stuff, we all understand the world is far from perfect.