Something like https://www.cbsnews.com/news/us-military-laser-shoots-down-c...
So lasers or turrets can work if you want to defend a military base in the middle of a desert, but not something that can be deployed in cities.
Apparently, the most efficient method so far is interceptor drones.
They aren't fundamentally different from a bunch of assholes sitting in an airplane 25,000 feet above you, flying above the ceiling of your flak and air interceptors, dropping a few thousand tons of firebombs on your town.
> I'm curious about how to defend against such drones.
Looking at what most of their targets have in common, I'd say that there's an easy answer to that - don't start wars.
So, your easy answer is incredibly difficult.
2. Drones are more effective in an asymmetric fight. The stronger , more developed side gets hit harder. Which is why Russia and the US is having such a bad time with them. They are both starting shit with countries that have far less to lose, and have far more resolve to fight.
So yes, it is in fact a pretty easy answer.