Chiming in as someone whom the GP comment resonates with: the point here is that you literally come to enjoy it less. The natural amount that you would eat isn't constrained entirely by health choices. I find finishing a single slice of cheesecake to be overwhelming: a second one would be actively unpleasant.
If you were following your assumptions here to their conclusions, you would conclude that people who eat unhealthily would eat cheesecake 24/7 if it weren't for conscious health choices. This is trivially untrue, no?
The original claim was that losing weight requires constant extra discomfort, and GP's (and my) claim is that this is false: you can move yourself (with initial discomfort) to an equilibrium that's more comfortable _and_ healthier than the status quo.
I feel the discomfort of constraining myself much less often now than I did when I ate like you. This is again trivial: if your preferences are aligned with healthy eating, you need to push against them less.