Consider responding to the substance of the comment instead.
Notice that, for the case of English, most speakers are not native, by a huge margin! Native English speakers are a biased minority, and with a lot of variation within. Not sure that an "average native" accent is a useful concept at all. I, for one, tend to find most non-native English speakers vastly easier to understand than many native speakers.
Maybe he wants to change the accent to a Texas accent, or the Queen's english, who cares, it's the ML part that's interesting.
I'm well aware, and this does not rebut any of my points.
> I, for one, tend to find most non-native English speakers vastly easier to understand than many native speakers.
That "many" native speakers in a language of hundreds of millions of speakers are hard to understand does not challenge the claim that a non-native accent brought closer to any native accent, much less the mean native accent, will for the large majority if listeners be easier rather than harder to understand.