According to a paper published in 2020 here, the specific energy and energy density are in line with what you are saying. But according to the article that Wikipedia cited here, sodium batteries show the opposite.
You’re probably right but it looks like there’s conflicting info about this currently.
In a post-scarcity society, you wouldn’t need money.
We could actually achieve that too. We’d just need to solve food logistics hurdles, homelessness, useless subsidies, bigotry, corruption, greed. Totally doable in our lifetime. /s