This may be true if by "basic science" you mean being able to rigorously derive the behavior of a complex system like a plasma from first principles. I don't have a PhD, but I have a Master's in Nuclear Engineering, and a lot of the plasma physics I studied while getting it was full of heuristics and phenomenological laws rather than rigorous or at least semi-rigorous derivations from first principles.

However, it's not clear that we need to know all that to achieve controlled fusion, and the fusion reactors that are being pushed for global funding are not being pushed as improving our basic science about plasma physics. They are being pushed as engineering efforts that will achieve ignition. As I said in another post upthread, we know what conditions we need to achieve for ignition; we just don't know how to engineer a device to achieve them. That's what ITER and these other devices are supposed to help us figure out.