Reasons they sometimes switch from long-lived Meet calls:
- Free up 200-300 MB of RAM when in call.
- Features specific to coworking (e.g. shared music DJing) or eng pairing (e.g. multi-way screen share).
- Presence when out of video calls. For example, you'd see if anyone on your team is in the Meet without having to ping each other. Leads to more unplanned hang outs.