Like when you send a .7z instead of a .zip or .rar to a friend or a teacher because that’s what your computer has installed and they’re like “Oh No, not one of those, now I have to install 7Zip” even though the same program that opens .rar also opens .7z I feel like people are way more annoyed when they receive a .7z
I had someone send me a 7z at work a few weeks ago and I got so elated that it wasn’t a zip! I did have to request IT to install 7zip but I’m so glad to have it installed now. It’s nice to see it being adopted more.