When you explain something away, the explanation is no longer about anything, for the explanation has deleted the thing explained from among the things that are real, and that are therefore amenable to explanation. But this means that the explanation itself signifies nothing. Statements of the form, “x is nothing but y,” then, are strictly meaningless. If there is no such thing as x, but only y, then there is no relation between x and y, and so no way to explain such relations. If there are no unicorns, then we might be able to discuss and explain the *idea* of unicorns, but not unicorns themselves, there being no such thing to explain. Explanations of fabulous things are all themselves fabulous.
So, technically, eliminative materialism is just meaningless noise. Thoroughgoing eliminative materialists do not disagree with this statement.
Proper reduction never explains away; rather, it increases the specificity and concreteness of our understanding of things. So, not, nor anything like, “thoughts are nothing but neuronal firings,” but rather something like “thoughts are manifest in neuronal activity.” That thoughts are manifest in neuronal activity deletes no jot of the ontological facticity of thoughts. On the contrary; it fleshes out that facticity.