Even if the grid was completely overhauled into some kind of futuristic design, our current understanding does not allow it to work with a majority of the power

Even if the grid was completely overhauled into some kind of futuristic design, our current understanding does not allow it to work with a majority of the power coming from distributed tiny producers (like rooftop solar) or majority renewable configurations. The existing examples you see of states or countries that claim to be mostly renewable, only work having the entire grid backed up with non-renewables for when shit hits the fan. We still don't have answers for relay desensitization and ferroresonance in particular. The bigger renewable producing projects pose less problems, but still don't replace baseload in the grid or serve to stabilise the grid. They can only follow the grid within a given tolerance. The worst part is that the powers that be are likely to ignore all of the above and roll out anyway. The grid will have already been syncronized by the things they turn off and things will for the most part roll along fine (service disruptions just becoming a part of daily life)... until something happens that requires a grid restart (think along the lines of a cyber attack or a natural disaster). That's when shit really hits the fans. Restarting the grid is a pretty manual and time consuming process, and renewables simply add too many variables to the equation to make this process possible. They would need to split the grid into lots of micro-grids, but then they would need interconnectors between each micro-grid that will be constantly tripping and incur substantial maintenance costs in normal operation. I am aware that you are not the original commenter I was responding to, but I can't help noticing that you did not respond to the main thrust of my previous comment though, about metallurgical coal.