The main reason for not appearing on the list is that there are practically no open projects in this field.
ITER (International Thermonuclear Experimental Reactor) apparently relies on open source software, but we could not find any open documentation for this project. (https://www.iter.org/newsline/-/3316) The Open100 project is similar. (https://www.open-100.com/) We have found only one big project that is really open and active: Paramek (https://github.com/ukaea/paramak).
Even in the case that any of the concepts discussed as 4th generation nuclear will work at all (there's a whole number of previous "new nuclear" concepts that have been tried and never went anywhere), it won't matter in the time most crucial for climate mitigation.
Nuclear is only financially viable because the government subsidizes it - usually to maintain weapons technology.
Solar and wind are almost absurdly cheap. It barely makes economic sense to build anything else.
If anything is going to make a dent on climate change and provide a way forward for sustainable energy generation it would have to be scaling up the share of nuclear (to 25-50% of overall share) with new and safer reactor designs that move away from outdated cold war technology we are still using.