[lopis]

If you invent an animal that is designed to grow muscle tissue for harvesting and isn't sentient nor suffers, you've solved lab meat, in an organic container. While many vegns grew a distaste for meat, that would indeed satisfy the vegan principle of eliminating suffering.

However, the reason farm animals are so cheap is because they are conscious, autonomous meat machines that you can order around easily.

* You do enter into another question here about whether brain dead or deeply disabled people are ethical to be eaten. Most people would say no.

[iamacyborg]

I think your latter point is a bit different to the topic at hand.

Cannibalism isn’t widely seen as distasteful because of the suffering involved, but because you're eating people.

Maybe a better question would be around eating dog, dolphin or to a lesser extent, horse meat.

[rhn_mk1]

Or the inverse: turning the brain dead into animal feed or fertilizer.

Closer to home: donating them to research/organ donation before they formally die.