A friend, back when he was a physics student, looked into harvesting lightning.

He calculated that it wasn't economically viable: tons of wattage, but for such brief timespans, that it doesn't actually amount to that much on a comparative scale. The cost of building the collectors and transporting the electricity (from ocean platforms) was much higher than the cost of using other energy sources. Iirc. It wasn't exactly a serious investigation by a team of engineers, but I basically trust his conclusion.

Maybe it will be more attractive in the future after we stop using hydrocarbons?

I know embarrassingly little about electricity, but wouldn't this also likely require significant advances in semiconductors to even be feasible?

I'm not sure about that. Drill some holes, pump some water, and geothermal power straight to the grid can be done. Harvesting lighting would require innumerable towers and even would require some trickery to get it hooked up to our power grids.

That’s not kinetic earthquake energy, though.

I think in an apples-to-apples comparison, you would need to attach some kind of device to absorb the kinetic energy from the fault.

A building-sized piezo crystal?

Country sized.

...and wait for the next major earthquake to even test it.

Or one clock tower and a flux capacitor...

For starters, the scythe keeps melting