The abstract is not an opinion, it is a summary of the key methods and findings written by the authors. It is the perfect place to get a short quote to outline

The abstract is not an opinion, it is a summary of the key methods and findings written by the authors. It is the perfect place to get a short quote to outline the main results of the paper. Now if we wanted to investigate the methods and results in detail, we certainly would have to read the full paper, however the main findings will not differ from what is in the abstract. You might find that the methods (and hence results) are not valid, and can come up with a detailed rebuttal, for that you certainly would need to read the full paper. However, I assumed here that the findings are valid, because even though I have access to the paper, this is well outside my area of expertise so I am not well placed to investigate the claims in detail and rather refrain from that.