> The reliability seems great until unexpected failures drops a large percentage of the national power supply in a matter of minutes (as seen in France, Sweden and Finland for example). Such events are more disruptive than cloudy days are with Solar.

That's a failure mode common to all large centralized power plants, not exclusive to nuclear. For instance, an unexpected failure (a triple fault on one of the transmission lines coming from the power plant) of a single hydroelectric power plant caused a country-wide power outage in two countries (https://en.wikipedia.org/wiki/2009_Brazil_and_Paraguay_black...).