Chernobyl happened because they didn’t have enough spare capacity in the grid to allow the more experienced day shift to do a spin down test, and instead of moving the test or ensuring the right people were on site overnight, they let the inexperienced night shift run the test. This, because management didn’t want to look bad, and they didn’t listen to the engineers.
Fukushima happened because their backup generators flooded and couldn’t provide emergency power to remove decay heat. They flooded because management didn’t listen to the engineers who spec’d a much higher (and more expensive) sea wall.
Three Mile Island can’t be blamed on management in the same way, but indirectly in that they allowed a culture of accepting defects to fester. Operators had so many inoperable or inaccurate alarms and meters that they were initially unaware of any problems, and then they didn’t trust / believe the readings they saw.
Nuclear power, when built and operated correctly, with strict procedural compliance, is incredibly safe. The U.S. Navy has over 7500 reactor-years of safe operation spanning over 75 years, with zero reactor accidents.
I am all for wind and solar where it’s feasible, but you simply cannot beat the density of nuclear fuel, nor its ability to provide 100% base load day in and day out. If you want sustainable green energy (and I do), it must involve nuclear power; fossil fuel plants cannot be replaced by anything else we currently know of.