I think for many healthy adults, the homeostatic hunger becomes unbearable after many hours. If you are such a healthy adult, then a lot of the hunger you experience is probably not starvation-homeostatic hunger.

That’s why many healthy people can train themselves to fast for multiple days on a regular basis.

Most of the hunger in my life is predominantly hedonic hunger, though the two hungers represent two ends of a continuum .. See https://www.livescience.com/54248-controlling-your-hunger.html

Q: So am I saying that over one or more days on nothing but juice, skim milk, raw vegetables, fruits, occasional protein powder[3], your body[1] can survive the fast without long-term [2] damage?
A: basically yes but with disclaimers:
[1] Note your mind may suffer if you are forced (by other people) to starve, rather than trained and willingly undergoing the fast.
[2] short term health effects are hard to ascertain. Stomach may growl. Energy level may drop. Sleep might be hard on an empty stomach. If practiced regularly, such fasting reactions may subside. I think most animals and our ancestors are used to such fasts.
[3] In my fasting diet, I exclude starch, fat and cooked food. See also ## acceptable foods during standard fast #fiber,starch

—how is this related to my 3-temptation theory? Hedonic hunger is the main driver behind the temptations. Take for example the wrong-time temptation. Timing is “wrong” because my body experiences no homeostatic hunger

—how is fiber related? Fiber doesn’t provide calorie so not addressing homeostatic hunger.
Does fiber address hedonic hunger? Not at all in my experience. Best example is chia seeds, which make me feel full for hours, but not satisfied.

Most of the “filling” or “fullness” or “satiety” foods promoted in mass media suffer the same weakness. In contrast, comfort foods [meat/fish, nuts, smoothie and dozens of starchy foods …] each satisfies a specific craving and provides satisfaction , the key factor of hunger.

In starvation mode, people eat roughage [grass roots and certain parts of tree barks] to satisfy hunger.

—How is smoothie related?
The ice in smoothie satisfy hedonic hunger better than fiber.

It is extremely important for short-term hunger management, but it has no effect on homeostatic hunger due to calorie.  Without ice, I feel hungry within 30 minutes.