You can have a private conversation over skype/IM for both quick questions up to moderate complexity.
Many meeting types you still want to do face to face (interviewing, hiring/firing, feedback, brainstorming, ‘analysis’, review/QA/progress check).
But the most common meeting type is “hey I want to talk to you about something” to ask a non-public office fact, and now you don’t have to ever do one.