Ask HN: What does Engineering culture in a super professional company look like?

When a company consists of a super professional developers and relatively small (WhatsApp, Netflix etc.), what does a company culture look like?

In this case, in my understanding, there's no need to make an extra communicational effort during code review for example. So you can say that a code is not good enough or even bad and not hurt someone else's feelings. In biggish companies one always should explain a little bit more and be more careful because there are developers with a different level of skills.

Or am I entirely wrong and there's no dependency?