The problem is when the user who sells it is a business or company who can’t be bothered to unlock the devices.

Guess this is a good reason for repairers/resellers or buyers to ensure activation status on any Apple device they get their hands on. Easy for repairers/resellers to ensure since they tend to be directly in contact with the company and make it policy. For general buyers, they have to be proactive before making any purchases over an Apple device. As it's easier to contact the seller in question while they are actively selling vs hoping they'll respond post-sale.

The refurbished probably shouldn’t purchase those machines then if it’s a known issue. There’s a tradeoff here, and needing the owner to run a command to reset the machine seems preferable to having them be valuable if stolen

If it's a known issue? Or if it's a potential issue?

All that will happen is that the second hand value of Apple devices will go down, because recyclers will assume X % are basically scrap.

They’re talking about it to the reporters? How is it not a known issue at this point?

No I mean if you buy 100 macbooks some will be locked and essentially worthless.

In that case the value of the entire batch will be lower.

So yes it's a known issue. But for each individual MacBook, it's a potential issue.

As you said, the problem is with the sellee. Apple is not the problem here.

Apple designed the system, they are at fault. simple as.

Recycler should make it worth doing for them.

Ah yes, because they have a massive incentive to do this

There's the incentive of "I'm confident that all my private data isn't on this machine any more", which I think matters.

this can be accomplished with a disk lock, no need to brick the whole machine

Sure, but in terms of how a non-technical user feels, I suspect that "it's still there, but trust me that nobody can access it" isn't as comforting as it just not being there at all. Thus an incentive exists.

Getting paid sounds like pretty good incentive.