Edge started itself on boot after a recent Windows update. It even had a little pop-up about how "helpful" it was to have it start right when my computer turns on so I can "get to browsing" faster. It's never been set as my default. Uhg.
And then on next update go turn it off again, since they'll enable everything again. Rinse and repeat for eternity. Or switch to Linux and be done with their shenanigans.
Run this after every update, specifically the tweak that uninstalls Edge. Makes things a lot easier. It also gives you the option to delay feature updates by two years and only install security updates on time.