The fact that it is happening to two softwares (Google and Zoom), suggests to me it is more a connection issue than any other.
You need to understand that video calls happen over a variety of network layers and protocols and ports.
This means:
- Using WiFi will be less reliable than hard wired to a modem that goes out of the house.
- Using VPN connectivity will slow you down and affect some software more than others. Some browsers use VPN IP hiding plugins and that can slow you down, quit any open browsers that might have VPN logging on, in addition to making sure your network settings aren't using any VPN, unless it is essential to use to get into a corporate or educational network.
- Using Proxies will slow you down and affect some software more than others. Apple menu -> System Preferences -> network -> advanced
- Using multiple different video conferencing software simultaneously may create too many resource issues. Quit what is not active at present.
- Internet connectivity is generally asynchronous. This means your speed to share something to someone on the other end of an internet connection is slower than your ability to pull a data file from them.
- If there is an Apple menu -> System Preferences -> Profiles panel, you have what is known as a mobile device manager. What this does in a corporate or educational environment is give the administrator of that environment more control over your machine. If the particular video conference software is not identified by the profiles, it may have certain attributes blocked.
- Simultaneous cloud backups. iCloud, OneDrive, Google Drive all have their own backup mechanisms usually managed through the system preferences. Network traffic from any other protocol that is simultaneous to your access for video conferencing will slow your down and cause dropped calls. This includes the use of Messenger, bluetooth connections to mice and keyboards (especially if done simultaneously with WiFi), connections to AppleTV, etc… Any network resource in use will create a bottleneck.
- Firewall software. Symantec has built-in firewall. Little Snitch lets you see what software is sending packets. Teamviewer, Anydesk, Apple menu -> System Preferences -> items checked, Splashtop, or other screen sharing tools will all create network bottlenecks.
