For one thing, natural bushlands would get overgrown.
Anyone who listens to world news knows that the south west of the US; California and Arizona especially, are prone to bushfires. So is most of the Australian outback where there is natural bushland areas. In Australia particularly, some species of tree are so integrated with the natural fire cycle that their seeds can't germinate without fire having swept through an area.
Now on the face of it one might say 'well good news! Just one more thing that abolishing lightning solves!' but that is a very narrow view of things.
For hundreds of millions of years (at least), fires have been started by lightning strikes and they literally clear out a lot of dead wood. The clean up the dead material on the floor of the forests and bushlands, and open up areas for new generations of plants and trees to start their own cycle of growth. This allows in part for evolution to be accelerated ever so slightly and for plant life to adapt to a planet changing on geological time scales. It also in turn wipes out a lot of other life that relies on the bushland but even that regrows with a new generation moving in to inhabit the bushland after it has restored itself.
To be sure, these lightning strikes can be massively dangerous which is why backburning huge tracts of land in the winter and early spring times (when the weather is not so hot and the fires are easier to contain) is such a good idea, and in a world without lightning every wildfire would have to be deliberately lit, even if done so by accident. Not doing so, because lightning is no longer an issue, would just allow a fuel load in bushland to grow to a point where a cigarette butt thoughtlessly tossed out a car window in the wrong place at the wrong time of year could be catastrophic. So, if anything, we would have to be MORE careful in our management of fire prone areas, not less.
As for the static electricity component, yes; lightning is a natural discharge of static electricity to reassert an equilibrium. That said, eliminating lightning would best be done by eliminating the ability to pick up that imbalance in static electrical charges in the first place, so it's unclear what impact the removal of lightning could have without removing the possibility of that imbalance would be, or even if it is possible to do.
All that said, lightning does seem to serve a useful function for natural bushlands across the world and as such removing it would remove a natural function of renewal for such lands.