The more we learn about other species, the more we realise that they are thinking and emotional creatures. I would no more want to see these experiments done on a human than on a chimp.
Do the ends justify the means? That's ethically extremely dubious, to say the least. Why conduct brain surgery on primates for neuralink? Where are we going with this, exactly?
As for comparing neuralink brain surgery to eating meat, that's chalk and cheese, and anyway millions of people don't eat meat.
A very useful area of research would look into how we can understand implications of procedures like this without needing to inflict hideous suffering on intelligent creatures - including humans.
Note: I'm not saying that all animal experiments are unjustifiable, but we absolutely need to improve how they are approved and conducted.