There is some truth to that, but at least the clients are not so terrible (see e.g. https://medium.com/bugbountywriteup/zoom-zero-day-4-million-...).

From a technical perspective I don't think anything groundbreaking is required, it just wasn't a market segment earning money before now, because why not just walk down the hall, or have a conference etc? Noone is saying a Zoom meeting can replace that, it is just a stop gap.