I don't really know anything about this topic, but I heard there are new designs of nuclear fission plants that are much safer and "unmeltdownable"? Called Molten Salt Reactors https://en.wikipedia.org/wiki/Molten_salt_reactor
I don't think it's molten salt reactors. I learned it as small modular reactors (SMR) which naturally cooled to safe temperatures if they lost power and water.
Sure, but we shouldn't be using only one type of nuclear reactor anyway -- we can deploy the SMR design for more populated areas where safety is paramount, and then run breeder reactors in uninhabited areas to convert the SMR waste back into fuel.
I'm pretty sure the only reactors that have ever failed have been designed in the 60s and early 70s (or earlier)
I'm trying to confirm it but I'm pretty sure no reactor designed later than that has had a meltdown and there have been significantly safer designs released in the last couple of decades.
I can look it up later if you're curious but I recall reading some interesting articles about it.