I don't see that a few Ashley Bickertons in a museum storeroom is such a big problem. But assuming this was a real issue, the remedy would be more places like the Underground Museum. You'd want more non-collecting institutions that take art out of museum storerooms and present it to new audiences, ideally in free spaces outside of predictable arts districts.
Below is Noah Davis' 2004(1) (2008). The gallery text quotes Davis: "Purple is to black people what Yves Klein's Blue is to white people."