He's absolutely right. The big picture of the Paris Agreement, and the reason for pulling out, was that it was an economic disaster. The Agreement was toothless, guaranteed no results at all, and would have cost the US tens of billions of tax payer dollars because reasons. Even if it were followed completely, we would avoid a grand total 0.2 degrees in warming over the next 83 years, and cost ~$100 Trillion dollars. Such a high cost for such a small alleged impact on the temperature, it's almost like carbon dioxide isn't a very powerful greenhouse gas ¯_(ツ)_/¯