Yes, cost is the issue. Everyone assumes that anyone hesitant about Nuclear power is focussed on the environmental or safety concerns, but that is wrong. The costs (and cost overruns) of the construction and maintenance of Nuclear reactors have been enough reason on their own to be bearish on Nuclear. I'm hopeful that new technologies, such as small nuclear reactions that can be built in a factory, will address this.
Environmental and safety regulations are supposed to be explanations for this rise in cost, not rival explanations to "cost is the issue" (since they take that as given).