I know school systems started using the system extensively for teaching. With this expanded use, a number of security glitches were discovered as creative hackers took their toll on messing with the Zoom system, e.g., a naked woman dancing as a fourth-grade teacher was initiating a call with her students (never a good thing).
See this announcement about fixes being applied to their system, Zoom releases 5.0 update with security and privacy improvements.
I expect what happened after the Virginia Tech shooting and alert and warning systems will also happen with video conferencing offerings. Dozens of new warning systems popped up and were being offered. At one point, there were 150 such companies offering warning services. Watch for bunches of new vendors entering the market in the next six to nine months.