It's important to separate the short range quadcopters that are easily built in small workshops from the long distance winged drones that can weigh several hundred pounds (like the Shahed drones).

The latter, as they're built by Russia currently, require a decent size facility to build en mass. It's not the kind of thing Hamas could build in their tunnel system, for example.

I agree with your second point that interceptors will become depleted though and this is a serious problem.