And a lot of engineering is involved to optimize that design, to build the towers as strong as is necessary to survive high wind loads while using as little material as possible so as to minimize cost. You're trivializing something that has a lot of thought put into it just because you don't really understand it well. I can guarantee you that more thought, simulation, and calculation goes into the design of windmill towers than goes into the average software project.
If it helps, I'm not a software engineer and have an unused degree in mechanical engineering.
They are pretty damn sure it is strong enough. It isn't the minimum material necessary to ensure that.
Concrete doesn't seem like the right material for this job.
The brochure of one company: https://www.max-boegl.de/en/downloads-en/116-max-boegl-hybri...
(Disclaimer: I know nothing about this and just report back what I read on industry associations' and manufacturers' websites)
Cost is the killer of so many renewable energy sources. There is tons of optimization going on for cost.
A lot of them are made in facilities that were built to make railcars (including big tank cars).