NG plants can't start delivering power in seconds. That's what "stabilization" means.

You're right that NG plants do play an important role in the grid today, but it's a "we predict that we'll need more power generated in an hour" role.

Gas turbines can be started within minutes. And majority of grids do not currently use "stabilization" within seconds. This sort of requirement is caused by the unreliable and unpredictive solar/wind generation.