This is why the first thing I do in my computers is disabling Defender via Registry or Group Policy.
It not only enables itself after rebooting the computer, it also ignore your exclusions every month or so when it has an update and removes files you don't want to.
Yeah, I know this is unsafe, but if you don't go to weird webpages, only install trusted software from trusted sites, doesn't use other people's pen drives, have weekly usable backups, and check every month the PC with other antivirus and antimalware there isn't so much dangers IMO.
It not only enables itself after rebooting the computer, it also ignore your exclusions every month or so when it has an update and removes files you don't want to.
Yeah, I know this is unsafe, but if you don't go to weird webpages, only install trusted software from trusted sites, doesn't use other people's pen drives, have weekly usable backups, and check every month the PC with other antivirus and antimalware there isn't so much dangers IMO.