It's quite possible that the positive effects of CO2 partially offset its negative effects, and by now it should be feasible to conduct and evaluate some experiments to determine what are the real consequences.
If we do nothing, and continue as usual without any changes, the positive effects of CO2 increases will definitely, at least partially, offset the negative effects, because we know with certainty that increased levels of CO2 increase world plant growth, including most food crops.
However, I would never recommend we do nothing. My recommendation is that we should fully exploit the benefits of increased CO2 levels and a warming climate. One benefit of a warming climate is increased evaporation which results in increased rainfall.
Increased rainfall, in combination with increased CO2, is tremendously beneficial for plant growth. Even areas that don't receive the increased rainfall, will still benefit, because increased CO2 levels are even more beneficial under water-stressed conditions.
With no shortage of water, a doubling of CO2 levels will increase the growth of most plants (C3 type) by around 35%. Under water-stressed conditions, that increase can be as high as 64%.
Of course, those irrational and emotionally biased 'climate change alarmist' will strive to think up any negative effects of increased plant growth, such as reduced protein, vitamins and minerals in rice which is grown in elevated levels of CO2, thus contradicting their own mantra on climate, that we should not do nothing.
We should not 'do nothing' whatever the problem. We should clearly identify and define the problem and then address it. If it is found that rice grown in current levels of CO2 is less nutritious than rice which was grown 150 years ago, then we should encourage everyone to eat whole-grain brown rice, which is always far more nutritious than white rice, regardless of CO2 levels.
If other crops are found to be lacking certain minerals and nutrients when grown in elevated levels of CO2 which are higher than currents levels, and also when grown in current levels compared to preindustrial levels, then solving the problem by reducing CO2 levels, which will inevitably reduce plant growth, is completely stupid.
If the nutritional content of plants is found to be lacking, after laboratory analysis, then we should address the problem by increasing soil health and fertility, and by adding to the soil whatever minerals are lacking.
OTOH, pollution of the lakes and oceans by plastics, combined with ever increasing amount of antibiotics, growth hormones and pesticides in the food chain, as well as clear-cutting of rain forests can't be beneficial in any aspect, and are most probably more harmful than CO2.
Of course. No disagreement there. All non-organic or non-degradable waste should be either recycled or burned in incinerators with strict controls of harmful emissions, excluding CO2 which is not harmful. The cost of such burning could be at least partially, if not fully offset, if the incinerators were designed to produce electricity.
