Yeah but it's fast enough, light, portable, repairable, can be setup directly in your bunker in the middle of the wood if needed, etc.

You're still thinking like it's 1990

3D printing will remain constrained by fragile centralized supply chains for feedstock until someone develops an effective practical decomposer/recomposer that can break down common plastics into their constituent monomers, oligomers, or other reusable chemical building blocks and then reform them into high-quality filament or resin on demand.

And then, the next step for deco/reco will be the metal frontier.

Unless you think you're only going to need a couple spools to get the job done before never using the thing again.

And where do you get in the woods all the other mass produced parts needed for a drone, like chips, sensors, engine, battery, ..? Unfortunately 3d printers ain't replicators yet.

So yeah, if you have special needs, modifying a special ops drone, or simple part printing, they are great.

Or like I said, distributed manufactoring.