I disagree under the following circumstances, which in my experience is the common case: You don’t know from the outset all relevant considerations that go into implementing something. Coding yourself is an exploration process of those considerations. Being shown a finished solution doesn’t let you see and understand all the considerations and the possible options that you’d have contemplated when implementing it yourself. When reviewing, you still have to do that exploratory thinking to weigh the possible options. And the fact that you have to do that exploration purely mentally rather than in a process of working with code arguably makes it harder (similar to contemplating alternative solutions to a Sudoku purely mentally, actuallu).

There rarely is a single correct way of implementing some requirement or feature. It’s a trade-off between compromises, not binary correct or incorrect like a Sudoku puzzle. The insights that the exploration give you may even lead you to implement something significantly different from what you originally set out to.