Energy density is an irrelevant metric. I don't care about the energy density of the source producing the power coming out of my sockets; I care about what it costs me.
Energy density is at best a contributor to cost, but if we have the actual cost there's no reason to use this dubious substitute. No reason, that is, unless you know the actual cost figures do not support your argument and are trying to dissemble.
The beauty of energy density is that you pay energy to get energy. You pay 1 kWh to get out 4 kWh in renewables. Thus you have 3 kWh available for society. Oil provides 9 kWh for society per 1 kWh investment. Nuclear provides 19 kWh for society. In developed economies we are about 12 kWh for society per 1 kWh investment. Thus going to renewables will cut society wealth by a factor of 4! The energy is not gone but it is redirected to maintain renewables infrastructure. If you live in the US rn, your renewables living standard will be equivalent to Mexico rn.
Money is quasi-energy. The petrodollar is not a joke. It literally binds the US dollar to barrels of oil. As everybody needs energy / oil, everybody needs US dollars.
Except it isn't. Energy is only one of the resources that goes into making things. Other costs, like materials, labor and cost of capital, are also important. Nuclear has the problem that these other costs are significantly higher than for renewables.
Energy density is at best a contributor to cost, but if we have the actual cost there's no reason to use this dubious substitute. No reason, that is, unless you know the actual cost figures do not support your argument and are trying to dissemble.