There is no ‘free market’ for allocating 1- and 2-character domains. The DAO is free to set whatever rules it wants for those unreleased categories.
Revenue is important for the DAO’s continued existence, and it’s important to empirically evaluate whether prices are appropriate to meet all the DAO’s goals and needs. ENS is first-and-foremost a public good, though, and considerations of revenue maximisation do not outweigh the goal of making it maximally useful to people. Thus, “we could bring in more money if we sold this” shouldn’t be enough to outweigh the public good of allocating a name for something that will be generally useful to everyone.
Then the same can be said to anyone else looking to acquire the name.