That is the case for base load generation, where the plant can operate near 100% capacity all the time. But that isn't were gas is usually being deployed; it being used for reserve generation. The economics of nuclear isn't as favourable in that application as it costs more or less the same to run at partial generation, or even no generation, as it does when it is going full blast.
I can imagine a future in which every data center has a little baby nuclear plant built right next to it. Watts per acre may become a significant measurement of density. Solar’s environmental impact is of course dramatically overstated by its opponents, but it won’t be when we scale it up and have to start slashing forests for it.
Fair point that renewables may have a practical expansion limit, but for the time being are, by far, the cheapest option so a data centre is still going to prefer that source of power to the greatest extent possible, thereby leaving gas/nuclear only as reserve — of which nuclear has not proven to be cost effective at. Geothermal, hydro, etc. are hard to beat, but where you aren't sitting on the perfect environment, generally speaking, wind+solar+gas is about as good as it gets on a cost basis.