We have already reached the point where solar and wind produce new MW of power cheaper than any other power source you can build.

Of course that energy generation comes with the caveat of being variable with sun and wind. It can still be a net benefit to the grid but the variability means alternative energy sources are still needed.

The cost trend of installing solar/wind plus enough storage capacity to provide steady grid power will eventually cross over to also being cheaper than other sources of energy. At which point the only reason to be against it is if you prefer artificially subsidizing another energy source.