We're alive for an infinitesimal blink of an eye before an eternity of annihilation. Brain science is still in the stone age. We should be flooring it with the research. Absolutely flooring it.
I wouldn't worry about what could or couldn't be.
Conscious humans are obviously special. But if we grew non-thinking bodies and used them for research, we could vastly accelerate medical science, research and development, and treatments. We could accomplish this with gene knockouts.
It's too "icky" for people, so it hasn't been done.
Or more literally, that they should make for themselves a lab rat, in the way The Thought Emporium is? https://youtu.be/Z_ZGq8Tah0k?si=UI18mJ4k5Xn4OtfD