Why does he need to be persistent?

He proved that he's a decent programmer by releasing a bunch of semi-successful open source projects. He worked at Yahoo. He has 900+ days GitHub streak. That makes him passionate about building things more than a huge chunk of programmers.

Not being able to implement a random algorithm on a whiteboard while applying for a front-end position has absolutely nothing to do with the lack of passion. Of course he gave up, and so would I if I was in his shoes.