Ironically, not only nothing made me think "I have got to buy Zoom stock" in 2018, IIRC around 2019 there were plenty of reasons to short Zoom. I wonder if they'd have survived if not for the pandemic.
Before the pandemic, zoom was a starting to gain market share over a bunch of the legacy conference software vendors, like cisco webex. They had their act together on the enterprise sales side and were getting traction via their freemium model ... just dropbox/box got enterprise traction even when companies already had things like SMB/CIFS or sharepoint. The UX was better for the same reasons many an HN didn't understand what advantages Slack has over IRC.