The paper you link to is a joke.
They claim a cost of utility scale solar as $17 / MWh and then claim a cost of utility scale solar with battery as $22 / MWh.
How much battery backup does that $5 / MWh provide? it doesn't say, but the answer is only a few minutes.
Look at the chart of page 28 of planned installations where it shows 22 GW standalone storage being added for 60 GW of solar and wind. That means the standalone storage being installed can provide 20 minutes of backup power for the renewable resources being installed.
The cost of a renewable system with battery backup that can guarantee power for even 24 hours would probably be at least 10X the cost of bare solar, so in the neighborhood of $200 / MWh, or quadruple the target cost of NuScale (based on the chart in this paper).
Guaranteeing power for 24 hours is not acceptable though. A system like that would have regular blackouts given the normal variability in solar and wind.
Unless someone is quoting a price on guaranteed sustained power delivery they are not serious. Try selling your electricity to a data center or any other commercial buyer and see how far you get.