What a lot of those projects show is the ability to get shit done. He has a BSc in CS. If you've got something similar it's a bug plus.
I have lost count of people that fail in parts of my interviews because they are too proud or scared to google for answwrs6 (after I specifically tell them that the problem is designed so that they have to search for some concepts).
I think what happens is that for a lot of us the imposter syndrome is very strong. Particularly if you frequent Hacker News, day after day you will see the 13 year old showing that made a PAXOS implementation in his new Codecademy clone during the weekend.
The reality is that HN is an echo chamber, where people are showing their best. Dont get me wrong it's really cool to see those projects but in real life, a "mediocre" HN coder is actually quite competent.
It's like how people get depressed because they see a stream of their contacts happy life on Facebook. Everyone is on vacation or celebrating some achievement. That's a distorted view of their life. And same happens in LinkedIn and any other network.