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
.7z is supported by most popular applications, and offers better compression than a .zip or .rar in my experience.
Unless you’re saying normally people rely on Windows Explorer for their (de)compression needs ? (･o･;)