Second Life's download page (secondlife.com -> DOWNLOAD) displays no links and offers no details or instructions about how to download the viewer if the user is viewing the page from a non-supported operating system.

This is rather confusing: most sites display all platforms, or provide an option to easily see all supported platforms' installers. Without any messaging it looks like the download page is broken.

Given: you are running an operating system other than macOS or Windows, such as Linux.

I am given instructions about how to download Second Life

I am presented with a page with no call to action or instructions, information about supported platforms.