At some point autologous blood transfusions weren’t illegal in sports, but they seem pretty clearly to me to be against the spirit of the game. What the makers of this device claim it can do seems at least somewhat analogous - both are a way of artificially capturing some form of energy produced by the body, then transferring it back into the body to avoid natural rates of depletion. If it’s not illegal it’s only because it’s BS, but if someone creates something that DOES actually do that, it seems like an obvious thing to ban.