Microsoft wants Edge to automatically open by default every time you turn on your Windows 11 PC
(www.windowscentral.com)
Although windows will still try to open edge and will blank out your default browser just to spite you. Absolutely infuriating.
I used to replace the edge .exe with a copy of firefox .exe, then write protecting everything in that directory and disabling scheduled updates and that seemed to work (for a while at least.)