BEVs are currently more expensive than ICE but BEVs will be less expensive in less than 10 years as the technology continue to improve. ICE technology doesn't have much room left to improve after 100 years so it's impressive that BEVs will surpass ICE so quickly.

BEV is limited by availability of raw materials. Copper, Lithium. It is actually predicted that there will be shortage of batteries for following decade, thanks to lack of available lithium and subsequent processing capacities and shortage of copper thanks to fact that we already maxed out output of current copper mines.

So there is no reason for BEV to be cheaper, more less it will keep being expensive or will get even more expensive than it is today.

If there is a shortage of raw materials, companies will work to get them to fulfill the demand.

There is literally not enough copper on Earth to get BEV going.