Carnival of Absurd

I was reading about this LOST BEATLES TRACK without really thinking of one thing or the other when I came to the very end, which reads:

McCartney would need the consent of Lennon's widow, Yoko Ono, and George Harrison's widow, Olivia Harrison, to release the track.

I had never really thought about it before, but why the fuck would Paul McCartney need approval from the widows of the two dead Beatles? Now, I'm all for their estates getting their share of the money, that's fine (and rather inconsequential in Beatle World, I'm assuming.) That's just the legality of things. But deciding to release a song is an artistic choice. A choice the artist uses to say "this is me/us." Neither Yoko nor Olivia were ever in the Beatles, were never part of the art. Why on Earth should they get to decide if a song gets released or not? Doesn't Paul McCartney's vote WAAAAAAAY trump theirs? In 1967 he could've recorded himself eating toast and released it; he was actually there, unlike Yoko and Olivia. I don't understand why their votes are equal here.

Of course I doubt either woman will really stand in the way of it. But the fact that they CAN is absurd to me.