This is simply not true. There has been tremendous ongoing incompetence and mismanagement in the reactor construction process in recent years. You may blame regulation -- that's the goto excuse for pronuclear people to avoid coming to unpleasant conclusions -- but the problem is that reactors are complicated things, and reactors with safety systems are even more complicated things (and reactors without regulation are complicated things that will almost certainly fail in unpleasant ways.) Building complicated things is hard, especially if all the institutional knowledge of how to do it, and the supply chains for the parts, have decayed away.

The huge advantage solar/wind have is they are simple and scalable. Installations consist of thousands, or even millions, of replicated parts. Experience builds up rapidly as the same damned thing is built and installed over and over. Nuclear doesn't have that.