I think the no-ego environment does a lot of work towards being more effective and increasing self-esteem. It's just so conducive to learning! But learning can be difficult especially if someone who's smart has never really been challenged as I can imagine being the case if you're doing advanced research where everyone has so much deep expertise.
Wow that's crazy! Was it cultural issues for example foreign born coworker who doesn't understand how respect in the USA works in text form?
That's an interesting point about high skill/experience/knowledge inequality leading to unequal code output. It seems that the less skilled person wants you to sign off on the code in which case they turn their brain off a little and defer to you. I think approaching the matter as a peer suggests you expect this person to learn from you and so you are giving them room to grow, explore and ask questions but this means they need to commit more time to solving problems because clearly if you just did the work for them then you'd arrive at a solution much quicker. Sometimes it feels like we are under so much pressure to produce that there isn't time to really master something just let your coworker flex their strength and the problem goes away.
Thinking back on your experience would you say that the extra friction comes from time constraints?