One reason is just that eating food is enjoyable. I limit the amount of food I eat to stay within a healthy range, but if I could increase that amount while staying healthy, I could enjoy that excess.
I think there are two aspects to the enjoyment of food. One is related to satiety. I enjoy the feeling of sating my appetite, and failing to sate it leaves me with te negative experience of craving food (negative if I don’t satisfy those cravings.
But the other aspect is just the enjoyment of eating each individual bite of food. Not the separate enjoyment of sating my appetite, but just the experience of eating.*
When I was younger and much more physically active I ate very large amounts of food. I miss being able to do that. I’m just as sated now with the much smaller portions I eat, but eating a small breakfast instead of a large one is a different experience.
This probably doesn’t justify some sort of risky intervention in increasing liver size. Food is enjoyable, but so are a lot of other things in life. But shifting to a higher protien diet seems like the kind of safe intervention, potentially even also healthier in other respects, that, if it has the side effect of being able to eat a little more food, could improve quality of life with minimal other costs. Potential costs I see are related to the price of protein relative to other sources of nutrition, the cost of additional food (if the point is being able to eat more, you’ve got spend money for that excess), and, depending on one’s moral views, something related to the source of the protien being added.
*I think Kahneman’s remembering vs. expereincing selves adds some confusion here as well. When we remember a meal we don’t necessarily remember the enjoyment we got from every bite, but probably put more weight on the feeling of satiety and the peak experience (how good did it taste at its best?). But the experiencing self experiences every bite. How much you want to weight the remembering vs. experiencing self is a philosophical issue, but I just want to note that it comes up here.
I agree that it’s plausible just from priors that ASI could find a way to eat the sun. The matter is there, and while it’s strongly gravitationally bound in a way that’s inconvenient, there’s nothing physically impossible about getting it out of that arrangement into one that’s more convenient to using fusion reactors or something.
But an analysis of how plausible the scenario is would certainly have made the post more valuable. There are plausible proposals for how to get the fuel present in the sun out such that it could be used more efficiently, and while it may be possible that an ASI might come up with a more elegant or efficient plan, there are some fundamental physical limits on exactly how efficient the process could be made.
Wikipedia has some discussion of possible methods: https://en.m.wikipedia.org/wiki/Star_lifting
That article says: “This energy could be collected by a Dyson sphere; using 10% of the Sun’s total power output would allow 5.9 x10^21 kilograms of matter to be lifted per year (0.0000003% of the Sun’s total mass)”, but this doesn’t take account of the possibility of using the collected mass to fuel fusion reactions that are then used to power the mass collection. What are the constraints on that process (my first thought is you have to worry about heat if you try to get the total power too high).
10,000 years sounds like enough time if you can get an exponential process going that uses the fuel harvested from the sun to collect more fuel. But any process will have some constraints, such as max temperature at which the various parts of your system can function, or the specific materials which your system is made of (do you have to build your fusion reactors out of materials harvested from metal rich bodies? can you use carbon converted into diamondoid nanomachines? can you get enough of those materials out of the fusion of hydrogen to keep the process going once it’s started?). Even if your fuel harvesters and fusion reactors can stand up to the high temperatures necessary to eat the sun in that time frame, what about everything else in the solar system? Does this process sterilize the earth of biological life?
Once I consider that there will be some sort of physical contraints on the process and also remember the fact that the sun is really big, it’s not obvious that even an exponential process of fuel harvesting from the sun will be completed in a 10,000 year time frame.