Ironically, I was just about to order a MacBook Pro 2019 because I'm still running Catalina and have no plans to update it.
I use an even older Macbook and an even older macOS. Of course, the browsers no longer work with the latest JS, so occasionally when I need to use some webapp I boot up a Linux VM and do what I need to do. With limited RAM even that's a pain, but it works for now.