I live in a country that is struggling to meet electricity demand as it is and our grid requires substantial investment to exploit our renewables, which are spread out and intermittent.
A switch to 100% EV on the scale and pace of Norway would absolutely flatten our grid. The only way we could do it would be to build lots of additional fossil fuel capacity with the intent of rapidly making it redundant. Which seems like a wasteful way to proceed.
The reason EVs have such a small impact on the grid in Norway is that they had already electrified their economy far above average due to the abundant hydro resources they been diligently exploiting since the 19th century.
Intelligent charging of EVs could make your grid more resilient rather than less. Especially if it is coupled with local solar. A friend of mine in central France has solar panels that he says provide almost enough for his EV on average. In the winter he has to take a little from the grid as well.
Norway has not switched to 100% EV. EVs are currently one third of the total private cars in Norway [1].
We are just close to all new private car sales being 100% EV.
The problems that most countries have with EV adoption are as much social and political as they are technical.
[1] https://elbil.no/om-elbil/elbilstatistikk/elbilbestand/
"Intelligent charging of EVs could make your grid more resilient rather than less"
Could being the important word here. With advanced load shifting and V2H all sorts of cool things could happen in the future. My point is simply that switching to EVs at the Norway's pace is a lot easier in a country with an abundant predictable renewable resources, which already uses 3x more electricity per person than any other European country.