There is zero reason to think 90% of people are going to die as a result of climate change.

The status of climate change claims is essentially:

• Average temperature is going up: definitely true
• CO2 levels are going up: definitely true
• The CO2 increases are the cause of the temperature increase: probably, but conflicts with previous periods in geological history of higher CO2 and lower temps, or vice-versa
• This is caused by humans: maybe
• This will cause problems for humanity: definitely
• This will cause existential threat to humanity: almost definitely not true
• This will cause benefits to humanity: definitely true

The notion that climate change is going to kill us all is simply false. It’s not what science indicates.