But they were gonna be so cheap it wouldn't pay to bill for electricity...
And had we made a standardized design, mass produced them, not built them on earthquake faults and with fail-safe shut down mechanisms, that prediction might well have come true. Instead, each nuclear reactor was custom built, required its own separate permitting process, and the Soviet-backed anti-nuclear "greens" managed to use the non-event at Three Mile Island to gin up enough opposition that building reactors ground to a halt.
We should still do that, come up with a standard design (or three -- say a standard large uranium base reactor, a standard thorium reactor and a small modular uranium based reactor) and mass-produce them. The climate change alarmists are deluded, but they have pointed out correctly that we cannot assume the earth's climate will remain at a climate optimum. Whether it gets a lot hotter, or a lot colder, we'll need more energy to adapt should there be a radical change, and nuclear is the only realistic source. (Heck, if we insist on building lots of AI, we'll need more energy even if the climate settles into something like the Medieval Climate Optimum for the next three centuries, and again nuclear is the only realistic source.)