This might not be climate change denial but the effects are basically the same.
I'm not sure there is any point in hair splitting whether someone wants to or accidentially lets humanity die out.
In either case you should ignore his research.
The majority of damage is being done by climate denying citizens and their elected populist governments that are entirely dismantling climate policies and carbon taxation or alternative carbon pricing measures.
His research methods are the foundation of environmental economics, so he should not be ignored (and won't be, DICE remains one major lens used by governments). The disagreement is over the numbers and specific damage assumptions which have been revised by others in new DICE model variants.