Export an abundant resource for a scarcer one seems win/win to me. Kind of the point of interstate commerce.
[0] https://science.nasa.gov/earth/earth-observatory/global-fres...
There is also an excess of electricity (thanks to gas peaker plants), so there are lots of transmission lines being built. (My property has an old transmission line on it, and then a new one perpendicular to that, solely built to try to do something with all the excess gas and then excess electricity being generated.)
So with that in mind... we'd probably rather our lake doesn't get drained, thanks, and is just left the way it is.
https://www.glslcompactcouncil.org/program-areas/water-diver...
That's 6 billion gallons a day. And if there were a supply of lots of fresh water, you could expect the consumption by agriculture in desert areas to go way up, so yes, it is entirely possible for lakes to get drained by schemes like thus, such as the Aral Sea disaster. Lake Chad and Lake Poopó are examples from two other continents of the same level of destruction.
The Great Lakes are part of the United States and Canada. If the United States or Canada would like to repurpose the water within them for some better use then that sucks for you
Draining the Great Lakes is not a good idea.