I was surprised to learn recently that the Internet Archive has no magical copyright exemption and the only thing stopping some of this stuff from being taken down is that they have a substantial legal team and the rights-holders are relatively indifferent. Trixter invokes the phrase “beyond economic recovery”.
It’s a far cry from the weird old days, when people tried to justify offering downloads by saying “It’s legal if you delete them within 24 hours!” or “It’s not a copy, it’s a copy of my backup!” or “Do whatever you want with this program – the publisher isn’t a member of the IDSA!”
But I reckon a lot of these downloads are still hastily-copied, incomplete, cracked copies originating from the pirates of the day rather than properly-preserved images of installation media. On the other hand, there’s something to be said if most of them actually work in-browser with a minimum of fuss.
