It is not rational aversion. Nuclear is currently 10,000 less dangerous per unit of energy produced than the largest sources of energy: coal, oil and natural gas. We could afford to let nuclear get 10x less safe, so that it becomes vastly less costly to deploy, and a very possible result would be that it would replace the largest sources of energy, and would still be three orders of magnitude less dangerous than the sources of energy it replaced.
Regulation is inescapable, because the maximum damage from a nuclear accident would exceed the value of the company operating the reactor. A rational business treats any liabilities larger that what it could pay as equivalent, regardless of how large they could become, and hence will underinvest in safety measures.
And I'm sure you will agree there is a great and sorry history of nuclear efforts failing to achieve their cost targets. At this point, it is clear that such targets are sales numbers, not something one should actually believe. One cannot make this history go away just by wishing, as nuclear advocates like yourself seem wont to do.
I agree fossil fuels should go, but that's not an argument they should be replaced by nuclear. It's the argument nuclear advocates used to be able to lie back and comfort themselves with, but then you all got blindsided by renewables and storage zooming past you. You have to address those now, not the old competition you wished you were still running against.
Of course regulation is necessary. My point is that current nuclear regulation is disproportionate to actual risk, and that this mismatch has made nuclear uncompetitive relative to energy sources that are demonstrably far more dangerous on a per-unit-of-energy basis.
Even compared to solar, nuclear has a stronger safety record when measured by deaths per TWh, and this is when taking into account the worst nuclear catastrophe, Chernobyl. I am not arguing that the future should be all nuclear, or even predominantly nuclear. I am arguing that the present regulatory regime reflects a mispricing of risk, particularly relative to hydrocarbons, and that this has pushed us into a suboptimal energy mix.
On cost overruns: the strongest correlation is with regulatory ratcheting, which also had harmful second order consequences for cost control from failing to reach larger scale construction, like bespoke designs and loss of construction continuity.
