Ed
You still can disable Defender manual, but not using a small program like Defender Control (https://www.sordum.org/9480/defender-control-v1-6/), which can do it very easily. Since August 11 such a program is detected as malware and removed from the PC. And now the registry key is removed for disabling Defender.
To switch off Defender manual, see https://www.wikihow.com/Turn-Off-Window ... Windows-10 or the last part of the article in your web link.
For uninstalling the new Edge, see https://lifehacker.com/how-to-uninstall ... 1844297854
I agree with you, Microsoft still breaks things in Windows10 and add things like all kind of Xbox utilities, we are not waiting for it.