We still die because of heatwaves and water and food shortages. It doesn't happen so much in the colonial empires of Europe and the USA, but it is still happening in most other places on Earth. Any attempt to export the lifestyle of average US and European citizens to the billions of other people would accelerate the problem even more, requiring an ever-increased rate of energy use to maintain livable conditions. The solution is precisely the opposite: dial down energy use (from all sources - industry, consumerism, travel etc) in the parts that consume too much.
Increased CO2 is creating higher temperatures, which in turn is disrupting temperature-regulation mechanisms everywhere on earth - leading not only to higher temperatures, but to more temperature variability throughout the year, more than has been seen in 10,000 years. It's also leading to more water remaining trapped as vapor, creating longer and more devastating droughts.
> Was increased CO2 bad for life on ancient earth? No, it was the opposite -- earth used to be an endless jungle teeming with life.
This only happens if forests and jungles are allowed to grow to use up the extra CO2. The opposite is happening today: everywhere in the world, jungles and forests are being actively cut down and the land cleared for agricultural use - capturing significantly less CO2 than an entire forest ecosystem.
> because they insist that the warming is the fault of humans, despite the fact that the climate seemed due to warm up anyway
They insist on this because we can actually quantify almost precisely how this is the fault of human activity. The rate of global warming is almost perfectly matched to greenhouse gas emissions. Historical ice age / warm age models entirely fail to account for this miraculous coincidence, and are in fact propaganda held up by massive industrial and financial interests that have an institutional lack of care for the long-term viability of current societies.