When people get excited about fusion as a source of energy, I’m always reminded of Henry Ford’s famous quote: “If I had asked people what they wanted, they would have said faster horses.” although apparently he probably never said that.
Fusion is that faster horse - promising a cheaper to operate firebox which when attached to a stream engine attached to an alternator can produce electricity.
This approach to generating electricity has been superseded by new technologies - first by gas turbines which removed the steam engine and then by wind turbines which removed heat from the process and now by solar PV which has removed all the mechanics.
I just can’t see any circumstances under which steam engines are “coming back” and becoming competitive for electricity no matter how cheap the firebox fuel is.
"I just can’t see any circumstances under which steam engines are “coming back” and becoming competitive for electricity no matter how cheap the firebox fuel is."
Industrial grade steam is still widely used and that probably won't ever change except to move from steam to supercritical CO2 and then only for power production. Most steam is used to do other things that are critically important to modern society. The biggest one is to make fertilizer without which we can't feed most of the planet. Your understanding of how industry works is fundamentally flawed.
Some fusion reactions release their energy almost entirely as fast moving charged particles.
You can slow down those particles against an electric field and harvest the energy as electricity directly. No steam turbine. No Carnot limit.
There are many kinds of nuclear fusion reactions
https://en.wikipedia.org/wiki/Nuclear_fusion#Important_react...
The lowest-threshold nuclear fusion reactions (deuterium–tritium (D–T) fusion, used by ITER, Commonwealth Fusion Systems) release up to 80% of their energy in the form of neutrons. These designs have to convert energy of the neutrons to electricity, indirectly using heat.
Since it is simpler to convert the energy of charged particles into electrical power than it is to convert energy from uncharged particles, an aneutronic reaction would be attractive for power systems. However, the conditions required to harness aneutronic fusion are much more extreme than those required for deuterium–tritium (D–T) fusion.
https://en.wikipedia.org/wiki/Aneutronic_fusion
You should check out Helion (direct to electricity) - https://www.helionenergy.com/technology/