So your logic is, only wind and solar can improve and nuclear can never improve.
Germany has spend billions over billions on the green transition for 20 years. Had Germany used the exact same money, to build as many reactor as possible as fast as possible and put them right next to existing coal plants they would likely be much further along.
Nuclear potential is insane. Like, just look at energy density. Nothing has as much energy density. And based on first principle, the total amount of resources required to do the transition with nuclear, is massively smaller then anything else.
Giving it the best possible shot and fullest possible support in the situation we are in, is just absolutely necessary.