Different markets require different tradeoffs. Flying things can tolerate higher cost, if it comes with a higher energy density, ability to charge/discharge quickly and (in some cases) higher cycle life. In this respect, sulfur-ion batteries might be viable even at 10x price compared to cheapest batteries on the market.
Grid storage is all about the price per kWh. Sodium-ion batteries ([1]) might become a good fit, while they are absolutely useless for electric airplanes / drones.