Well, honestly it's hard to imagine any situation where it would be economically viable to extract He-3 from lunar regolith and bring it back to Earth any time soon and that's ignoring the fact that we still can't yet build a fusion reactor to burn it in. D-T fusion will be more practical for a long time because we can breed the fuel pretty easily by sticking lithium in a fission reactor. That same breeding reaction is the one that ultimately produces He-3 since the tritium decays into He-3, but it's way faster/easier to just use the tritium instead of waiting around for it to decay. Helium fusion also has most of the same materials issues as D-T fusion and a higher ignition temperature, so really it's not particularly ideal.

Outside of fuel for fusion, radiation detectors and a few other minor applications there's not much use for He-3. The more interesting possibility to me is the idea of extracting He-3 on the moon and keeping it there, using it to fuel a fusion reactor powering some sort of sci-fi type lunar city/port. Since it's available in relative abundance on the moon directly and doesn't have to be bred indirectly it starts to make sense as a fuel.