No the construction economics are still mostly the same. UCAVs with the range and capacity to replace manned tactical aircraft are only marginally cheaper. MQ-25 unit cost is in the $150M range. No country can afford to build a lot of them.
The small, cheap "swarming" drones have very limited range and endurance. Useful in some limited scenarios but only if you can first find a way to deliver them to the target area
I posit that the costs will continue to decrease as mindshifts change--right now (or more precisely, around the time these drones were designed and purchased) we think about drones as being "unmanned planes" and planes are supposed to be big, reliable, and expensive and the military procedures and culture is calibrated to minimize losses of these planes. As expectations change, I think costs will decline as well which will feed back into a change of expectations (time will tell).
Regarding "delivering them to the target area", it's pretty easy to conceive of a larger transport craft managing delivery.
What's your point? We already have that. Large bombers are used to deliver cruise missiles close enough to the target area. Cruise missiles are drones by another name. But they're hardly cheap. In fact they're getting more expensive.
There have been proposals to build conventionally armed ballistic missiles to fulfill the prompt global strike mission. The problem is that if Russia / China / North Korea detect a ballistic missile headed in their general direction they might misinterpret it as an incoming nuclear first strike and retaliate accordingly. A very dangerous game.
Also it's rather pointless to deploy any sort of "drone" from a long range ballistic missile. It would need a complex and heavy braking system to slow down enough during re-entry to allow for controlled flight. Easier to just hit the target directly with a re-entry vehicle.
The point is that AI has the power to change the ecology of war. Cruise missiles occupy a niche, and yet they haven't obsoleted combat aircraft, so clearly they aren't "drones by another name"--drones serve a purpose today and will continue to diversify (including a blurring of lines between "drone" and "cruise missile"). Anyway, this conversation has taken a defensive tone, so I'll duck out.
The small, cheap "swarming" drones have very limited range and endurance. Useful in some limited scenarios but only if you can first find a way to deliver them to the target area