> Human society is not ready to grant intelligent animals sentient or human status.
It's the intelligent animals that aren't ready for "human status" and sentience has nothing to do with it. The natural order of things one of 'strongest makes the rules' and that's true regardless of sentience. Humans, however, decided that constantly struggling for dominance wasn't a very efficient way of doing things and figured that if everyone played nice life could be better. The agreement to 'play nice' is human society and things like rights and freedoms are the benefits to joining in. Humans are still free to opt out and follow the natural order, but as it turns out all of the other humans together are pretty strong and more than capable of exerting dominance, usually by putting the offender in a cage.
In other words, society isn't about sentience or intelligence, it's about agreeing to a social contract. That contract puts restrictions on you beyond the natural order (e.g. you can't just beat someone up because they are weaker than you) but also gives you benefits too (e.g. people stronger than you aren't allow to beat you up). If a human doesn't (criminals) or can't (children) sign up we generally throw it in a cage or keep it as a 'pet' (usually respectively). The same is true for nonhumans, the only real difference is that society is opt-out for humans and (theoretically) opt-in for them.
This wasn't opting it; it was a farce. It's a bunch of humans trying to force some animals into an agreement with the full understanding that the animals don't understand it and will never even try to honor it. The goal basically being to change their label from 'animal' to 'criminal' (I don't think they're even trying for any stage in between) in hopes that the latter will provide some benefit that the former doesn't. If a nonhuman is willing and able to enter into the human social contract, then I honestly think there will be a place for it. Sure there will be xenophobes as there always are, but I think society as a whole would view it as an interesting and worthwhile experiment. Until that time, however, if you want animals to be treated better make that case not some nonsense personhood case.