But my point is people seem to assume sentience is a byproduct of high level intelligence, which might not be true. Maybe we need to focus more on "what is sentient", "what makes a sentient thing sentient" first and discover the basic elements of sentience.
If we can formally define sentience, or reverse-engineering sentience, or build a "MVP" or "bare-minimal" sentience. Thing would be much easier discuss.
Here are some random thoughts: Self-awareness might be a consequence of evolution - it might be more optimal to grow self-awareness than other perks to survive. Just like occasionally using reflection in programming could solve hard problems elegantly. Sentience and emotions might also be consequences of evolution - they can be seen as efficient and power tools to communicate, people can efficiently affect a lot of people with their emotion, without conveying rationally by words.
Here's a random idea: Build a complex simulation game, but with relatively simple creations with some evolving capability. If we try to manipulate the environment enough to let self-awareness and emotions to be optimal solution.
Are insects sentient?
If so, could we build less intelligent but sentient AI, on par with insects?
If so, is it unethical to torture such intelligence for fun in simulations?
If we can define or create something as "minimal sentient", the following discussion on ethics would be more clear - since now people are talking past each other with completely different understandings.