"found that approximately 97% of them support the consensus position"

versus the more correct

"found that among abstracts expressing a position, approximately 97% of them support the consensus position"

Doesn't strike me as particularly 'wrong' or 'literally lying'. They are looking at where the consensus position lies on a particular idea that doesn't need to be mentioned in every abstract in the field. A paper to do with global warming can analyze reality without stating a cause for global warming in the abstract; that doesn't mean that the paper should count against one consensus position or another.