I agree. Even if Ferrari think one of those is better, they probably don't think they're a lot better, and they're under contract, and meanwhile Raikonnen is the "bird in the hand worth two in the bush". I think Ferrari will continue to keep their eyes open, and maybe take Sainz/Pérez to dinner a couple of times.
Now if Redbull hadn't locked in Max V, they'd have been all over that.