I don't see how the "attractiveness" of helium-3 is anything non-zero. If you can't even fuse deuterium with tritium, which is the easiest thing there is, helium-3 fusion goes out of the window.
DT is certainly easier to fuse, but it presents very difficult, IMO likely intractable engineering problems. D3He would finesse those problems (neutrons, material damage, tritium breeding), and potentially enable direct conversion of fusion energy to electrical energy (or, perhaps, more volumetrically efficient transfer of thermal energy to coolant). So IF the physics can be made to work, D3He could end up being more practical.
The company to watch on this is Helion, and perhaps Princeton Satellite Systems.
The company to watch on this is Helion, and perhaps Princeton Satellite Systems.
https://www.helionenergy.com/
https://vimeo.com/553784697