Core help links in Windows used to use an embedded version of the system browser (at the time IE) originally https://en.wikipedia.org/wiki/Microsoft_Compiled_HTML_Help. If they wanted to do that today for the above reasons they could do the same with WebView2 which is the OS embedded version of Edge. Instead they are launching the external instance of Edge which can still be screwed up for reasons outside the OS's control (such as an experimental edge://flags option that causes a crash on launch).