Keyboard Keys Degredation

This is just a general question, i just never noticed until now. But once keys get 'oily/shiny' is that it? the matte feeling never comes back correct? Kind of know the answer but just seeing if anyone has some homemade tips that can get that matte/new feeling back. At this point im assuming theres a matte coating and its just degrading over time. Not that it matters, love the keyboard. Just hate that oily feel/slick feel.