GDP = C + I + G + Xn = W + I + R + P

(To grossly simplify the single-nation macroeconomic picture, at least)

C = consumption I = investment (the first one) G = government Xn = net exports

W = wages paid to labor I = interest on capital R = rent on resources and real property P = profit to entrepreneurs

consumption ~= wages, so if wages go to zero, the economy massively shrinks unless government steps in with something like taxation to fund UBI, sovereign wealth fund distributions, or direct universal ownership.

Wages could go up, it's just in the form of trillionare paying another trillionare a trillion dollars a day. GDP would be looking rosy!