Earlier quoted context omitted.
Lunar resource extraction is unlikely to be viable for anything other than building on the moon - ever. The quantities of energy involved are simply too high.
I highly doubt that’s true, sending it back to earth is fairly cheap. Getting stuff to the moon can be expensive, but there will def be certain resources worth sending back. For instance, 10Kg of gold is worth $750k. Probably could just send that back with a few astronauts. That’s not to include the possibility that there’s certain manufactured goods that could be cheaper or only possible to produce at lower gravity.
Landing on the moon is a very different endeavour than simply reaching Earth orbit from Earth. In order to refuel and reuse rockets on the moon, you'd need to build out all the infrastructure for doing so first, not to mention the resources necessary for continuous operation. Even getting running water on the moon would be a huge logistical and infrastructure challenge, let alone operating a launch pad.