Alright, I guess it's time to talk about it.
I do remember from my first attempt at watching Korra, ages ago, that this is a thing. This is probably the first thing about this show that I straight up don't like - which is admittedly hypocritical, since I accept widespread metalbending and can still logically trace why and how regular joes can generate and manipulate lightning.
Lightning is my favorite bending technique from the original series! Metalbending might be a close second, but brilliant as its introduction was, it could never beat how flashy, dangerous, and impactful the lightning bolts were. And that was the best part, to me: how dangerous the technique was for everyone involved. One false move, and the bender would be destroyed, or the redirection would fail. Even a missed bolt would still set you on edge, as it would likely hit the ground or a wall and utterly destroy it. Technologically sound as this is, it kind of takes that bite out lightning for me.
There's more people bending lightning in this single scene than in the entirety of the original series.
It's no dealbreaker or anything, but I would definitely leave this little detail out of the fanfics I'll probably (inevitably) write about Korra sometime in the near future.