Any Macs made in the past 5 years require exactly one step: clicking "Erase All Content and Settings", which is exactly the button anyone would push when trying to wipe a machine before giving it to someone else.

Things may have been more complicated before that, but Apple has made it as easy as it possibly can be now without telling thieves to just start grabbing every Mac they see.

Not past 5 years - MBP 2018 with Catalina didn't unlock when using that. It's possible that it was a bug, but after previous owner nearly threatened lawsuit for "phone mobbing" (I wasn't the first person trying to call them to remove it from FMM) I kinda gave up. Needed to use the machine right away and broken FMM belonging to locked-out Apple ID didn't stop me from that.

Yes past 5 years. That’s what the Apple documentation says, since it says it applies to any Mac that was T2 or newer. That doesn’t mean that it would have worked this way 5 years ago. Software improvements with macOS have undoubtedly made the process simpler than it used to be.

"Erase All Content and Settings" did not exist in macOS Catalina. Back then, you had to manually boot into recovery and reinstall the OS that way, which unfortunately did nothing for Activation Lock, and was a confusingly advanced procedure to expect end users to perform. Now, someone just has to go into settings and click that button and macOS will handle everything.

FMM?

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