Twenty first century military supremacy may go to whoever can produce the most best drone printers. Meaning whoever can produce the most best drone printer printers.
Printing is good for prototyping and if you are making small numbers/need to have a distributed manufacturing (because of bombs falling on them).
But for mass producing a solid design, 3D printing is the worst solution, because it is slow. Injection molding would be the fast (and cheap) way.
Drones are just one part of the equation. They are a “last mile” solution, which makes them very strong on battle fronts and come with a defender advantage.
We still require logistics to transport the drones into effective range, intelligence to know the most effective targets, and military grade wireless communications to guide the drones.
If the intelligence is good enough long range missiles can kinetically disable drone production or drone stockpiles.
3d printers making 3d printers making drones is a key plotline of the Bobiverse novels.
Not just drone printers, but also field soldering robots. Many components are still through hole. Putting tray of PCBs and let robot solder the joints would be game changing.
3d printers are wonderful for rapid development, but are much slower than industrial serial production.
Quantity has a quality all of it own, and all that.
Ukraine is doing wonders managing tons of different producers and models, but Russia production capabilities have always been a problem.
Ukraine was in the lead with their interceptor drone. Unfortunately now russia has refined their drones to not be multiple pieces sticked together, and has added small jet engines.
The new drones are both too fast for interceptor drones and might even survive a hit thanks to the body made from a single sheet of metal.
Now the new russia drones cost about double, but intercepted rate went down from 90+% to about 55%. Math says the new drones are more than paying for themselves.