The question of "can the grid handle it" is a complex question. ERCOT has some fun gauges on a dashboard view. I think those gauges only answer some things but not other important ones. E.g., there could be transmission bottlenecks within the grid that aren't represented on those charts. And such bottlenecks might only become a problem if generation were to fail in the right place(s). If we were to rely on importing from outside the grid, what are the limits of the DC ties--bot just their current flows, but their remaining capacity? There are also factors that aren't "the grid" but which will get lumped in with the same concept, too, like each independent plant supplying energy to the grid. (Those were the precipitating problem during Icepocalypse.)