So, in looking at this from a communications standpoint, this argument would conserved through, or even highly through. Here’s how I, as a communications student and as a communicator, come to that conclusion.
Oliver cites multiple sources, embraces both the pro’s and con’s, uses primary and secondary sources, uses appropriate language for the subject matter, and formats/speaks about the material in a manner this his target audience understands. He has a clean argument, and line of logic. His argument is well explained and supported, and it’s clear that it’s connecting with his audience.
Now, obviously there are people who disagree with his argument, or otherwise have issues with it, but in terms of being a well explained, thoughtful, and communicated speech he would score highly.
I will add that while his argument may not cover everything about Modi (and I’m certain it doesn’t), it gives a good base of knowledge about the “issue/subject” (in this case Modi). People who watch the speech now know where to direct their line of questioning, and they can begin to formulate their opinion on the matter.