True wireless power transmissions have been around for a century. A simple one is any radio transmitter, and why special precautions have to be taken when close to a transmission tower of TV and radio since the power levels a person gets in their bodies is dangerous when too close.
Beaming power from space using concentrated light/microwaves is being examined as part of ideas/plans to have solar collectors in space and “beam” the power to collectors on the ground. Pity any person/aircraft that crosses that beam.
The USA and Russia tested atomic weapons in the belts around the earth to see the effects of charged particles being introduced into the bands. Both countries discontinued the testing because it hurt themselves as much as the other and realised they could not use it for energy transmission, for disruption of radio signals or any other purpose without damaging themselves.
Tesla’s power transmission does not obey the laws of physics the way it was presented. Tesla was many things - a brilliant man, an eager showman, creator of ideas both possible and impossible in the real world. He is remembered mainly for his work on AC transmission and his showmanship. Many myths of his exploits mar the reality of the brilliant man.
His world wide power transmission has been known since Tesla’s time and any company in the past could have built them and made a fortune, there was no conspiracy to stop them. Now there was a reason they were not built.
Now it seems we have a man or group of men who are going to test the theories and lets see if it ends up more than a simple radio transmitter principle for wireless power or if there is some new science that can be demonstrated that has eluded man for around a century.
My money is on no more power transmission than would be predicted by a radio transmitter principle. Basically what our understanding of physics would give us and that would mean it would not be effective. To transmit enough power for the world from the tower to the world would mean electric fields enough to ionise the atmosphere and the subsequent consequences.