Source: just wiped and sent back a MacBook Air to my old workspace. My colleague finished the macOS setup and logged in with their iCloud account. After resetting it again (to re-do the setup in the way they wanted) it was locked to my account. So not even installing macOS and logging in to iCloud will bind the machine to you.
Imagine doing that with a machine you bought second hand and the original owner can’t be reached anymore.
https://support.apple.com/en-us/HT208987
"Other ways to disable Activation Lock"
"Activation Lock is disabled when you use the Erase All Content and Settings feature."
Apple confirms that the feature works exactly as I said and exactly as users expect. I've used it myself, and it does work.
Users running software that is several major versions out of date will have a more difficult experience, since that button did not exist, and they would have to first remove Activation Lock before going into Recovery Mode to manually format the Mac. Those are the remaining steps that were linked several comments up from here: https://news.ycombinator.com/item?id=34505523
Apple has made the process as easy as it possible can be now, identical to the process used to factory reset an iPhone.
I’d argue if you can wipe it (which requires your iCloud account approval), install it as someone else, login with that new iCloud account, then reset it and it suddenly reverts back to the previous owner, something is wrong or very unintuitive.
The problem on Mac it seems is that there are two official ways to do it. One proper way (the “Erase All Content and Settings”) and one other way (the way we did it, boot into recovery and format it, then go through setup with another iCloud account which apparently just temporarily lets another user use the machine). On iPhone there is no user accessible recovery mode so that can’t happen there.
If you go through recovery, you can delete the content, but when you go to reinstall, you will be prompted for the credentials for the user tied to it.
Meaning, you can delete, but you can't reinstall without being prompted for authorization by the account that currently 'owns' that computer.
The IT department has no idea what kind of password that user was using, and they have no idea what kind of valuable data is on that machine. If that user's password was just "password", that IT department is also going to end up in hot water if they didn't wipe the machine before handing it off to a third party when all that proprietary data ends up in the wrong hands.
If wiping the machine before getting rid of it is "extra work", then that IT department isn't doing their jobs to begin with.