Incorrect. They actually purchased them and could download them, DRM-free. (At least if the other services listed are like Bandcamp.) You should archive them yourself after downloading. The fact that you can download them again from the server, or maybe stream them, is an additional service, it's not the thing itself.
That being said, when something is not sold anymore, I'd say it's fair game to torrent it or upload it wherever.
I disagree with the latter notion. If you hold the rights to something, it should be you who gets to make the shots on how - or whether or not at all - you would like to monetize said thing.
Perhaps you plan on taking a break for a couple of years and then sell the item again?
Just because someone else really wants your item, does not automatically give them the right to access it or make it available to others, if you as the rights holder disagree with that.
True, strictly speaking, and it's also what the law says. But I'd wager that >90% of the time that is not the case, and that often the rights holder is not even aware that they hold those rights.
Well, who knows? Even if that is the case, I would argue that the correct way to go about is to first talk to the rights holder and ask. One cannot just assume or wager.
There's little I can imagine that would warrant a third party to just go ahead and access/use the item of the rights holder the way they would like, just based on some assumption.
That being said, when something is not sold anymore, I'd say it's fair game to torrent it or upload it wherever.