It’s just an example of the fact that programming is far more than code. It is also managing dependencies, build systems, making architectural decisions, developer support, etc.

It is very possible to be good at slinging code and bad at everything that is required to support deployed code.

Based on geohotz history, I wouldn’t be surprised if he falls in that bucket - hacking and algorithm skills are great but don’t lend themselves at all to building twitter. That’s why it is foolish to pretend like one guy is great or even good at everything.

I think the more likely explanation is that he's just not as familiar with frontend web development and react, so he underestimated the difficulty. He was asking for help on Twitter for how to make pills inside of a text field. His failure was caused by a knowledge check rather than a skill check.

Totally fair! I think it is more of a reminder that making impact at large companies can be hard even for competent people.