This concern stems from math that is based on the idea that everyone will be charging their EVs during the day, while A/C is running and peak office power draws are online.
This is ... an unlikely scenario, at best. The closest we might get would be a post-rush hour spike, when late afternoon heat is spiking home AND office A/C use, if everyone plugs in every day.
But even this is unlikely, as the affected markets generally have lower off-peak pricing, and EV owners tend to pay attention to that. I can say that if my market charged 3x during the day what they do at night, mine would be set to use the charging window feature for sure.
And further into the future, bidirectional charging will become commonplace, allowing those plugged in during the day to contribute to the grid, and draw back at night when power is plentiful.
In short, there's not a substantive cause for concern at this time. And as you can see from the history of the petroleum industry: When there is a hunger for energy, companies will arise to satiate it.