No, there isn't enough lightning. Global lightning output is around 1% (or less) of global energy consumption. There is nothing about the technology that unlocks lightning bolt harvesting as a new feasible power source. We could do really similar things with simple lightning rods that have been around for centuries.
I think many people over-estimate how much energy exists in a bolt of lightning. They're incredibly powerful because they transfer the energy in a millisecond or less, but there are only about a billion joules in an average lightning strike. For reference, that means you would need to get your home lightning collector struck by lightning at least once a week in order to satisfy your home energy needs.
Also, an important component in lightning is an upward convective current bringing warm and cooler air together, which cloud seeding would not affect. Clouds or rainclouds themselves don't cause lightning, which is why not all clouds/raincloud types are associated with lightning.
Nitrogen fixation maybe? Lightning breaks N2 so it bonds with O2 into NO2. Rain then brings it to the soil to be taken up by plants. But lightning does this at a much smaller scale than microorganisms do, so maybe not too important.
