I think that what we 'have to think through' is what did 'they' know then vs. what we know know. Quite a time spread and how do you go back (and at what cost?) 'un-do' what seemed like a heck of a good idea 30-50 years ago?
And there in hangs the tale?

Assuming you want to hit a light switch and have the bulb turn bright here in the PNW and much of southern Kalifornia during the late summer (that's where the extra power generation ends up) pull the power generators and replace them with what?
I have no idea what the 'right answer' may be.
fae