I dont want to repeat myself a thousand times, but what you say is not true. It is 28 years and he has lots to show - so nothing is wrong.
There is also lots of experimental proof. Also done at independant labs that had his reactor for over a year without Mills supervising the experiments. And of course the Rowan University replications etc.
He may not have finished an energy producing device, but he has a theory that gives the structure of molecules with analytic equations with great precision. This is something no one else on this planet has achieved so far - not even 70 years research of thousands of physicists.
Of course you can say this is all nothing. Like it is nothing that mankind landed on the moon. No one replicated it for 40 years - no moon bases - nothing. Must be a scam and brought us nothing. And the cost!! Billions of dollars for nothing.