Correct me if I am wrong, but each of these "steps" is a research project in their own right. The AviationWeekly article mentioned D-T fusion for the Lockheed

Correct me if I am wrong, but each of these "steps" is a research project in their own right. The AviationWeekly article mentioned D-T fusion for the Lockheed prototype and includes a diagram with the caption "blanket absorbs neutrons to breed fuel and transfer heat to turbines". This "blanket" will be tons of material that would be activated during operation and would have to be disposed of at EOL. Also, modern materials include many trace elements within the main molecular lattice such as cobalt, chromium, etc in steel and in some ways might be more difficult to process than used fuel rods. I worked in the nuclear power industry decades ago and I don't recall the how the energy of fusion neutrons vs fission neutrons compared but I thought that in general fusion neutrons were significantly higher. Most power fission reactors also have neutron moderators which help to reduce the activation and embrittlement problems. Nevertheless, core components in fission reactors are already experiencing neutron embrittlement and has been a concern. I'm not trying to be negative on fusion power but these overly optimistic reports have to be read with a critical eye.