You can't safely assume all your employees are properly assessing the risks unless that is their actual job. If you only allow what you know then you can reason about your risk.
Engineers aren’t clamoring to get into the kinds of companies where IT needs to pre-approve software for their workstations.
Of course, after years and years and hundreds of thousands of engineers, the whitelist is pretty robust.
I don't know for sure, but I bet Zoom has been on that whitelist, and "banning" is removing it from that whitelist.
Our laptops are configuration managed, force upgraded, and surveilled, but we all have root and IT has never stood in the way of "power user" behavior. The extent of the frustration in engineering is that their management processes sometimes eat CPU. My understanding is that most of the Valley is like this.