Regardless of how cheap it may be, the storage of solar power is still a big problem. If we're on the topic of cost trends and batteries, the price of lithium is up ~500%.[1] That's making batteries more expensive than in the past and given all of the demand for them I don't really see it going down any time soon, at least not until new lithium mining plants are built mainly in South America, which still isn't likely to drop prices again in the near future.[2]

1. https://tradingeconomics.com/commodity/lithium

2. https://www.economist.com/the-economist-explains/2022/06/09/...