But there’s no way she’d have just “known” this, and it’s just another hurdle to non technical users. Why should you have to know that Ubuntu is a downstream distro of Debian to install a program?
It's also something that is answered effectively with the very first Google result for an obvious search: https://www.google.com/search?q=should+i+install+deb+or+rpm&...
There are a few ways round this but they would generally require action on the part of all the software suppliers who post packages via websites. In your example it wouldn't be hard for MS to figure out the Ubuntu users and send them just the right link and likewise several other Linux distros - I guess it's still not worth it.
Maybe this is an area where a JS library for websites would avoid each one rolling their own and thus make the experience better across the board?
Just say "teams doesn't work well on my computer, it's very poorly made. Can we use jitsimeet? It's much easier for me." and them drop them a jitsi link without waiting for their response.
Teams is the official video chat at my company, I've been successfully ignoring that for more than 2 months now. At this stage, jitsi usage is starting to spread to other teams.