Have you ever thought that MrDrNose probably switched to .7z to force at least a tiny percentage of people to get just a bit more computer literate?
A decent archival software is an essential tool on any PC. And it so happens that on Windows, 7zip-gui is the de-facto standard for most archival operations. Learn it.
If you can't get it to work, download NanaZip from Microsoft Store. It's a 7zip fork. Click-click and you just missed an opportunity to learn how to set up file associations.