The paper was conclusive but the BODY of work does not in the majority agree, given the link. There is no consensus, yet. Also, "The study has not yet been peer reviewed" so maybe take it with a grain of salt.

Is your latter conclusion re herd immunity being impossible supported by the literature, or at least a mathematical model? If R0 goes below zero the community is protected. The vaccinated fraction might have to be large in order for this to happen, but that's also the case for the measles. You're stating that it doesn't matter what this fraction is, even if one person isn't vaccinated they're eventually going to get infected.