But this launch system still needs the projectile itself to be a fairly complex rocket capable of delivering several km/s of delta V and of steering the payload onto a desired orbit. That still implies electronics and mechanical systems onboard even if you're carrying only bulk cargo.
Electronic chips themselves are rather good to withstand acceleration - can be packaged well. Mechanical systems for simple rockets could also be, well, simple - e.g. first orbital launcher of France used pressure-fed engine.
