Data centers are a pretty good match for nuclear because they run 24/7 and use a fairly constant amount of power. Solar is cheap in terms of amortized price per kWh but then you need some other solution to supply power at night or when it's cloudy, and the price of that has to be paid on top of the cost of solar.

Meanwhile nuclear costs what it does in significant part because the number of new plants is low which requires the cost of designing new reactors etc. to be amortized over fewer plants. But if you build more of them that changes.