This actually happens with people preferring books to ebooks or vinyl records to MP3 files.
But anyway, I'll respond with a second hypothetical.
Gasoline Gal is married. She expressed a preference that her husband remain faithful to her, and being old fashioned, even made sure that her marriage vows promised faithfulness.
You are not trying to convince her to accept either hydrogen engines or uploading. Rather, you are trying to convince her that she should not prefer that her husband remains faithful to her. At most, she can prefer that her husband remains faithful to her as far as she knows. As long as she does not know and cannot detect his unfaithfulness, it causes no harm to her. She objects, of course, that it could cause harm in some indirect way (such as increasing his chance of passing a STD to her), but since this is a hypothetical, you say "if your husband cheats on you, but because of some circumstance, this doesn't increase your risk of STDs or otherwise cause you any physical harm, and it causes you no mental damage because you don't know about it, is he wronging you? And is this a situation you shouldn't prefer?" You say that he has not wronged her and she should have no preference against that situation. Indeed, you're not even sure it is meaningful to have a preference against that kind of situation. She disagrees. Who is right?
This is related to the fact that utilitarianism is bad at handling blissful ignorance situations although the problem is by no means limited to utilitarianism.
This actually happens with people preferring books to ebooks or vinyl records to MP3 files.
OT nitpicking: books you can resell or lend, no such luck with ebooks, they work without electricity, quick shuffling through pages is easier with books, MP3 distort sound (though not perceivably at higher bitrates), so this was not such a great analogy. But yes, your point is valid.
"Hi," said Galaxy, "Are you Fuller Chen? I'm here to see your 2018 Chevy SS. Is it still for sale?"
"Sure," Fuller replied, "let me open the garage door for you." [Garage door opens.] "What's your name?"
"I'm Galaxy, but everyone calls me Gal." Galaxy walked around the car. "Looks great. Not a scratch or a blemish."
"Would you like to take it for a test drive?" Fuller asked, opening the passenger door for himself and reaching the key out to her.
"Yes, thanks," said Galaxy. She adjusted her seat and mirrors, then started the car and eased it out of the garage and onto the residential street. "Wow, this car is really quiet. Is it a hybrid? I didn't think they made a hybrid."
"Nope, not a hybrid," Fuller answered. His smile made her think there was a joke in there somewhere.
She took it onto the main road and put the pedal to the metal. The response was rapid and forceful - and eerily quiet. "This car is too quiet," Galaxy objected. "What's going on here?" She slammed on the brakes and pulled into an empty parking lot.
"It's a fuel cell!" Fuller announced. "Pop the hood, and take a look! Retrofitted it myself. It's a labor of love, but I need to cash in all my major assets for my business start-up. That's why I'm letting it go at the price of an ordinary SS. And as you have seen, the performance is equal to or better than any conventional engine."
Galaxy looked under the hood. It sure did look like a fuel cell. "We have a problem," Galaxy warned, "I admit, I am impressed with the performance, but ... I'm looking for a car with an internal combustion engine. I need to hear the roar of the engine, feel the vibrations, and know that I'm being propelled by something that's literally exploding."
"Oh, if it's a roar you want, the car already has a speaker to generate noise for pedestrian safety," said Fuller. "I could modify it to make the same audible sounds as a traditional internal combustion engine."
"No, listen: my nickname is Gasoline Gal. I grew up working in my father's auto repair shop. I was the engine specialist. Internal combustion is what I know and love. It's what I want. Not a simulacrum, but an actual internal combustion engine."
"But I can make this car behave the same as perceived from inside the cockpit as well as from outside the car. You mentioned the vibrations of a regular engine. It would be a simple matter to add a vibrating cam or two. I tell you what, I'll make those modifications for free and you can test it by taking it on a tour. If you can't tell the difference from the driver's seat, buy the car."
"No," Galaxy answered, "you're not getting it. It's not about the behavior, it's about the underlying reality, the underlying cause. I reject your test, and I insist on looking under the hood. I love internal combustion engines. Fuel cells are merely kinda cool."
"Is it about gasoline versus hydrogen? Hydrogen is widely available nowadays. I don't know why so many people are still prejudiced against it," said Fuller.
"No: it's not about the materials, it's about the internal processes. And it's not that I'm against electrolytic energy conversion, it's that I'm wild about internal combustion."
"Hmm. You came to love those engines by working with them and getting to know them. Maybe if you worked with fuel cells, you could come to feel the same way about them," Fuller suggested.
"Maybe," Galaxy conceded, "but I'm not willing to wait and see. I'm not looking for motivational reform. I want what I want."
"But maybe your desire is irrational," Fuller suggested. "Are you sure that driving an internal combustion powered car is really a terminal value for you?"
"Heck if I know!" Gasoline Gal answered. "But it is already clear that this car, despite its acceleration, reliability, style, and reasonable price, just doesn't do it for me. I need to go find a good old-fashioned car to buy. One with an actual internal combustion engine."
And the next day, she did. She paid a little more and the acceleration was a tiny bit less, but the acceleration came from the right source.
----
The Question: Is there good reason to suppose that Gal's desire for internal combustion is irrational, and if so, where's her mistake?
The story is an analogue, along a narrow dimension, to my real subject. I flirted with a horrific pun in there - bonus points for pointing it out - which reveals it. But you might want to save the inevitable critique of the analogy for later. I plan on two more posts. In my next post I'll try to say something about the language (semantics) of desire; then in a third post I'll lay out the analogy.