Photocatalytic splitting of CO2 on liquid Metal could one day be really really effective and it doesn’t need an additional energy source.

Currently it’s just play pretend.

In Germany the parents get asked if they want a burial but in my case most parents decide that the hospital should handle it. It is then disposed of in a mass grave.

One of the proposed reasons the Romans adopted Christianity was because the church would help collect taxes. For all of the middle ages the church would be one of 3 instances that “run” a state (estates). Taxes were a big part of that job.

That means the answer to your question was just roughly 1700 years ago.