It seems weird to me to use online chat to talk to someone right next to you. I've done it in some situations to avoid disturbing others but it's pretty inefficient compared to face-to-face talking.

The good thing about online chats is you have a history of the conversation to reference later.

This is worth its weight in gold. Add to that the ability to selectively broadcast the conversation to potentially-relevant people without mutilating the concentration of non-interested parties. Add to that the ability to forward that info to new team members years after the conversations have happened and potentially years after the originator of the answer left.

I mean, why is there a need to chat while working? Why not go to the kitchen to chat?

Code review seems pointless at a company with a defined code conventions.

"Code review seems pointless at a company with defined code conventions."

I don't mean to disrespect you, but either you are you are very green or are living in a completely different universe of software engineering than I am. It's interesting to hear this viewpoint.

Code conventions don't cover good algorithm design, good architecture, common implementation patterns, edge case coverage, etc.