I mean, we obviously need to do both. The conversation in the thread is about nuclear, which is a supply side resource. DR and demand shaping do even more to enable truly renewable resources. Why do the demand shaping to enable nuclear when renewables are cleaner and cheaper?
A lot of science around trees and forest management has gone this way. Forest used to be seen as competitive areas that needed to be thoroughly managed to be healthy. Now we know that’s not true at all, and overall would be better off if we just let them be (in most, though not all cases). Same with the idea that trees communicate with each other and share resources. This was dismissed and ridiculed for a long time, but has now been pretty resoundingly proven true. Peter Wohlleben’s The Secret Life of Trees talks a lot about this.