On: Wu Riddles: Hardcore tech-interview style riddles ...

[amichail]

Do you know anyone who is good at programming in general but not in solving these puzzles?

Software engineering is not the same thing as (clever) algorithm design.

[elq → amichail]

Writing software is essentially solving problems.

Some of these puzzle/problems are stupid, but if you do not know how to solve problems well and frequently you probably will not be a good (let alone excellent) software developer.