FO3 must have been in the first wave of "game devs have children now, so every AAA game is about father-son relationships". I wasn't sick of the trope yet, and actually got really into the story FO3 wanted to tell. I played it close to release, did the self sacrifice at the end, and generally hold that experience in high regard.
Then I loaded an earlier save and tried asking the robot to do it. I belive I had a mister handy follower, been a while, but of course it also refuses with some silly rationale. Bethesda games are both so immersive and yet full of these peeks backstage that constantly expose the artifice of it all (and the latent biases of their creators).
It didn't exactly ruin the magic of that first run, but it did make any subsequent plays feel very... toy boxy. I had kind of the same experience with Elden Ring and Skyrim, now that I'm thinking on it. That first playthrough is like watching LotR, then every other one is like smashing Gandalf and Orc action figures together (or playing any of the LotR games lol).