Thanks for the comment. Yes and no.

On the job seeking perspective, what you said is right. Typically what people do is signing an NDA, but even with that, the question/solution still sometimes leak on the Internet.

On the learning scenario, it's sorta true, but mostly sharing the solution would ruin the motivation, at least for me personally. If I know there's a solution sitting there, I wouldn't be interested in repeating it again.

I know it's sorta silly... But my mind works best when I only focus on the problem, and how to solve it. As long as I know there's a solution, I couldn't stop myself looking at it whenever I was stuck at any tiny bit.