Eh. Private chats are the equivalent of walking over to someone's desk and asking them about something. Posting in the team chat is the equivalent of standing up and asking something out loud so that everyone in the vicinity can watch and listen. The latter IS expensive and distracting.
That being said, it is important to recognize which conversations would benefit the whole team. Asking about changing something in the architecture should probably take team input, but asking why something is broken to the engineer who made that change is fine to do in a private chat.
That being said, it is important to recognize which conversations would benefit the whole team. Asking about changing something in the architecture should probably take team input, but asking why something is broken to the engineer who made that change is fine to do in a private chat.