"Time Boxed" needs to mean boxed on
both ends. If a meeting is scheduled to start at 2:00, it starts at 2:00. Not 2:05, not when the last person wanders in, and not when the organizer figures out how to run the projector. The implied task there is that any setup should be done prior to the start time.
Nothing is more frustrating than company cultures which allow the "meetings never start on time, so I'll show up late" / "not everyone is here on time so I'll wait a few more minutes" death spiral. It's like a game of chicken to see who thinks their time is more valuable than everyone else's.