I have seen in other interviews where he elaborate further that other people can do covers of The Beatles songs and it will sound good without producing examples but never heard a good cover version of Rolling Stones because the song is intrinsic with the performance of Mick Jagger.
However personally great cover version of The Beatles is rare (the only exception is Every Little Thing by Yes which may well be better than the original). In fact PJ Harvey/Bjork cover of I Can't Get No Satisfaction is amazing reinvention of that song so I don't even agree with the idea that you can't interpret Stones song differently https://www.youtube.com/watch?v=Dg39hJIhzAk
The reason is that The Beatles were great performers as well and rock music the performence is just as critical as the song and this can't be replicated in cover version of the tune. There is a definitive version of the song unlike in concert music where there is no definitive performance).
I would perhaps agree with him if he simply just stuck with melodically/harmonically/texture the Beatles had more substance than the Stones and left it at that without discussing about reinterpreting by different performers.
The most I can agree with him is that you can have competent cover version of Beatles song that is no where near as good as the original but still enjoyable because the songwriting is great enough to be enjoyable no matter who performs it but if a person tries to do a cover of The Stones, unless you radically change the song (ala Bjork/PJ Harvey) it's hard to be decent because it relies on people replicating the idiosyncrasy of Mick Jagger. Even if they replicate it, it would sound like imitation/parody (similar to people trying to imitate Dylan's vocal)