Lithium batteries are made of lithium to a point that there is a lithium supply bottleneck if we want to use lithium-ion batteries as the base chemistry for the green transition.
It will take time to mass produce things regardless, but I imagine Sodium has far fewer bottlenecks.
The lithium bottleneck idea comes from people who go "looking at the current lithium supply we would run short if we instantly started producing 10x as many batteries as we do today", completely ignoring how markets work.
It's great if we can get a chemistry that avoids the need for lithium, but it won't be a showstopper if we don't.
It will take time to mass produce things regardless, but I imagine Sodium has far fewer bottlenecks.