Ok, timescale is 4000 years. Holocene is 12,000 y. CO2 has been relatively stable, and also temperature, compared to all the previous post ice age cycles, when there was noticable decline in both, leading on to the next ice age period. What is different this time? - This time, human beings have spread over the world, as hunter gatherers, and horticulturists, and are using fires to cook food.

We homo sapiens are here in Australia by at least 40,000 years ago. Nothing you say explains the rapid warming in last 200 years in both CO2 and temperature , an altogether different time scale of change.

Later on semi-permanent agriculture we had 4000 yr ago, with bigger city state civilisations, and the warfare and collapses that was part of it. Other causes of variability, well known to climate scientists - volcanoes, 3 earth orbit periodic irregularities, and rise and fall of human agricultural civilisations and their direct environmental effects and recoveries from them. Data is still being accumulated. Its not that climate scientists lack mechanisms to explain, the problem is that detailed data is lacking, for the smaller slower fluctuations in temperature, prior to our extremely big exponential fossil fuel binge ramping up in the last 200 years.

There is actual work going to study this, you just haven't asked the right scientists, or even googled it. For instance Climate Change during the Holocene (Past 12,000 years).

https://link.springer.com/chapter/10.1007/978-3-319-16006-1_2