Solid-state batteries might not be cheaper at first. But once economies of scale from mass production efficiencies kick in, they will be.
One thing that goes under-appreciated about EVs is that even though they are winning today against gas-cars on reliability and cheapness, they still have years of improvements and cost reductions ahead. By the 2030s, they will be vastly cheaper & better than fossil fuel cars.
China is already making decent cars in the $10-15k price range; this battery tech will make that even easier. It's also making these cars with good Level 3 self-driving tech. There is a vast unserved market in the Global South (& huge chunks of the Western world) for cars like this.
The standard global car of the 2030s will be Chinese-made, an EV, self-driving & cost about $10,000. Anyone who still thinks gas cars have a future in this world is a dinosaur who can't see that asteroid streaking through the sky & about to hit them.
Solid-state EV batteries are coming sooner than expected after another breakthrough
Go, China go!