It's a shame Apple has decided that if the launch agent or daemon lives in the System folder that means the user/admin should have zero control over it. I should be able to disable any launchd job on my computer end of story.
You’re very entitled to your opinion, but it should be fairly obvious why this isn’t reasonable from their perspective. Put another way, let’s just say I think apple is glad you’re not making decisions about how their operating system should work. It’s an OS built for users, not those who wish to have iron control over everything. Allowing that would be disastrous for most users just to appease the very small percentage who’d want that.
If that were possible, malware would shut down a mountain of services very quickly.
Right off the bat, XProtect, MRT, Gatekeeper, amfid, system updates, telemetry, MDM...