Yes/No. When you can build stronger materials under computer control, then computers allow you to build smaller/lighter airplanes.
OTOH, it isn't the computer itself that facilitates the improvement, its the computer as a part of an improved process, that couldn't be improved (that way) without the computer.
So. Currently 3D printers are toys. Did you ever even see the Sinclair computer? (I forget its model.) It was a toy. But that didn't make it totally useless, and other computers were not only much more useful, they became both more useful and smaller and cheaper over time.
P.S.: There *do* exist 3D printers that aren't toys. They also aren't cheap, and the ones I've information on aren't small. But different models can print in Titanium, Aluminium, Concrete, etc. I don't know whether they all require hand finishing, I expect so. OTOH, this is early days yet.
Do you know how long the laser was called "The development looking for a use?" It was over a decade. Of course, the original lasers were big, expensive, and difficult to use. They required specially polished rubies, cryonic conditions, and they only worked on microwaves. They were also called masers, but that word has dropped out of existence, so now we have uv lasers, ir lasers, green lasers, and for all I know X-ray lasers.
I doubt that CNC machines will ever drop out of use. I expect that they'll continue to become easier to use. But they won't be used for small runs for much longer. Already Car companies use expensive 3D printers to print their design prototypes, and I'm sure there are many uses I haven't heard of.