The Tesla grid scale system made that money by stabilizing the grid, essentially providing storage for time periods below 15 minutes. It in no way provides the kind of storage that is needed to use solar or wind power as baseline production.
For battery storage to be cost effective in general it has to be quite a bit cheaper than it currently is. The cost has been declining, but people who expect exponential curves to continue forever are generally disappointed. It may or may not hit a stable floor before the cost is low enough to actually replace baseload power generation. What it is likely to be good for is to get over the load hump between dusk and bedtime for solar -- but that requires a lot less storage than being able to carry the whole night. Especially in winter (when the nights are longer), and especially if we expect people to switch from carbon-based to electric heat.
The issue is we need to be building things to replace carbon right now. Even if batteries become cost effective in a decade or more, that's too late. And there is no guarantee of even that.
That's kind of the point. Better to have it and not need it than need it and not have it.
And even if batteries become cost effective in a decade or more, that's when people start installing them at scale. It's not as if you could replace the entire grid with them overnight either.