I suspect those weren't included in the studies because they aren't grid scale yet.
Consider that "one of the biggest batteries in the world" stores 129 MWh, enough to sustain the US grid for one second.[1] (Of course, it can't discharge that quickly, so we really need four thousand of them to sustain the grid for one hour).
For comparison, the current capacity of pumped-storage hydroelectricity in the US is about 550GWh[2], the equivalent of about four thousand of those facilities. And we still don't have enough storage to replace nonrenewables with solar.
Batteries like that one won't reduce the actual price of energy storage here until Tesla builds thousands of installations in the US alone. And it would take hundreds of thousands worldwide (along with solar generation) to replace nonrenewable generation.
But it is a promising technology. If many are built quickly, and the reported financials prove accurate and scalable, we might have cheap grid-scale storage in ten or twenty years.
1: According to the US Energy Information administration, the US grid generates about 4 billion MWh per year.
2: "[In the United States] forty-three PSH plants with a total power capacity of 21.9 GW and estimated energy storage capacity of 553 GWh
accounted for 93% of utility-scale storage power capacity (GW) and more than 99% of electrical energy storage (GWh) in 2019."
You can easily run a grid on 60% renewables with essentially no storage at all. We have a long way to go before 60% of the world's primary power consumption is switched to renewables.
I see we're not discussing the same thing. I was talking about the cost of solar and storage, Germany uses more wind and a lot of biomass and hydro.
But I'm happy to discuss this too. That 50% figure is a peak (achieved when conditions were favorable) and ignores imported electricity.
According to [1], renewables accounted for 41% of power production in Germany in 2021, but only 16.1% of primary energy consumption.
AIUI, that difference comes from (a) imports and (b) the fact that primary energy consumption also includes heating and transport, two sectors that often aren't directly powered by electricity yet, but which must be before an economy can stop consuming non-renewable energy.
As you said, this trend will keep on going.