It's all incredibly ridiculous. If this man were really on a "dopamine fast", the conversation still would have ended, but not in the same way.
It would have ended because he would be wiggling around on the floor and making noises like a dying cat. His basal ganglia, starved of dopamine, would not be able to make any of the neural connections they need to coordinate any of the muscle movements in his body, including the muscles needed for speech. This guy seems like he was more interested in informing this person that he was fasting than actually keeping his "fast".
This incident reminds me of the Desert Fathers, the early christian monks who lived in the desert in Egypt. They took fasting very seriously as a way of keeping their religious purity. Many of their parables caution against keeping your fast for show. Here's one:
"Once two brothers went to visit an old man. It was not the old man’s habit, however, to eat every day. When he saw the brothers, he welcomed them with joy, and said: “Fasting has its own reward, but if you eat for the sake of love, you satisfy two commandments, for you give up your own will and also fulfill the commandment to refresh others.”
From "The Desert Fathers: Sayings of the Early Christian Monks" https://www.amazon.com/Desert-Fathers-Sayings-Christian-Clas...
You can read more about these monks here: https://en.wikipedia.org/wiki/Desert_Fathers?useskin=vector
And here is a famous quote from Saint Anthony: “A time is coming when men will go mad, and when they see someone who is not mad, they will attack him, saying, 'You are mad; you are not like us.”
This is relevant because a lot of the things in this book have to do with removing distractions. The monks were doing it to pray.
Okay that said:
Something I've been noticing about myself lately, which could just be reading comprehension decline?
I tend to skim what people write heavily. So much of what people write seems completely pointless. ChatGPT and other LLMs have really laid this bare. You can take a simple statement like "tell this person that I can't make it to dinner", and it will expand it into several paragraphs of niceties, but the actual information is the same.
I've noticed that it makes it difficult to switch back to information-dense reading, and to actually read all of it instead of reflexively skimming it to try and glean out the seed.