It is understandable from Manu's or other experienced entrepreneur's perspective, ideas are important. I don't deny that. That is because they have been through startups over and over again, these people understand the work that goes into the company months/years post-idea-conception.
I would say a good portion of the people who are reading this site won't fall into that category. As a matter of fact, very few people do. Most of us are just budding entrepreneurs trying to our feet wet and trying to find our way to "make it".
If you feel you fall into the latter category more than the former, read Manu's post with a grain of salt, it's _not_ really meant for you.
I'd argue (with my limited knowledge) that it's more important for young entrepreneurs to know that ideas are a dime a dozen. By the time you come up with it, 10 other people have thought of it as well. What separates great ideas from good ideas is that you have a clear competitive advantage that can allow you to out-execute those other 10 people. This competitive advantage can be your passion, skill set, domain knowledge, connections, etc.
So if I have to sum it up, and to modify Manu's post to fit the eyes of the budding entrepreneurs:
It's not the idea that matters, it's the people + the idea that matters.