Linux (GNU/Linux or whatever) doesn’t even have the concept of a system web view. The closest you might get to the notion is probably WebKitGTK which is perhaps the GNOME idea of a system web view, but it’s nothing like WebKit on macOS or WebView2 (or MSHTML in the past) on Windows for popularity or availability.

As a user of a desktop environment other than gnome-shell, I only have webkitgtk-6.0 installed because I chose to install Epiphany—it’s a good proxy for testing on Safari, which Apple makes ridiculously expensive.

Yeah the closest thing you come today is arguably WebKitGTK, which is known for being not exactly great.