He keeps saying light does not have a speed and that it merely has a rate of induction through mediums. This is a semantic difference not really a substantial difference from current models. Maxwell's wave theory of light is understood to be a model so is not an insane assumption but a model only. Time is itself not constant, so speed is just a measurement. The terminology that is convenient is what is used. Time, light and speed are all actors in a play that is still being studied. This is plain in Physics courses right at a bachelor's level or high school, not a secret. In that level of Physics that studies the nature of light and matter, nothing actually has a speed any more than light does; but it is convenient to use that terminology for many purposes. Aether is an idea that comes up now and then, and it can be interesting but has not so far been observed and so far doesn't provide more useful models than wave particle duality models for most purposes. Aether is getting some attention though. There is a new related term called the 'Quantum vacuum' which is one approach to the aether concept, and that may lead to refinements of current models or new models.
In fairness, I am not really suspecting a government cover up of fusion. It is very difficult to conceive of cold fusion technology. I also do not think Tesla is like an alternative to Einstein or Maxwell. He invents a lot, and its true that his idea of a tower could work to harness the difference in electrical potential between the air and the ground. I do not know how well it could work, and he never finishes his experiments with it. To me it doesn't seem better than hydro dams or geothermal power or solar, but I am guessing.