It really is disappointing to see such narrow minded thinking, it really is.
Yes, the costs are high at the moment for buying hydrogen by the kg, as it takes a lot to get it to that end user product. But why not use nuclear power instead of natural gas or gasoline in the production of hydrogen?
Hopefully R&D into the production of hydrogen will continue, making it easier and cheaper to produce, and if that means a nuclear powered future, then so be it. Either way (hydrogen or battery) there are still downsides (nuclear waste v disposing millions of batteries), there is no getting from that.
Production of hydrogen is already mature (it's a roughly US$100B industry). Hydrogen is a common industrial gas, you can phone up BOC and have bottles delivered if you like.
It is unlikely that Hydrogen cars will spur a break through in hydrogen production (A $100B industry will already be able to fund decent R&D).
Nucular power to modern safety standards is very expensive, hydrogen production by electrolysis is inefficient.
The other elephant in the room with hydrogen is difficulty to transport. Either you cool to cryogenic temperatures, or you compress to crazy high pressures. Both methods take a lot of energy and require expensive specialized tanks. Even then you can't fit many car's worth of fuel in a truck.
This also poses issue with storing the gas on board a vehicle. Toyota Mirai has two tanks that have a combined volume of 122.4L. These tanks are cylindrical and have a 25mm thick carbon fiber wall, so they are not convenient to package into a car. They are filled to 70MPa (700Bar). (For comparison you tires have under 0.3MPa of pressure in them, and a scuba tank has around 20MPa). Even with all the above, the car still has a range of less than the biggest battery Tesla, and cannot be charged at home.
Note that many hydrogen dispenser in California are only filling tanks half way (to 35MPa), making the picture much worse.