@Limax Without knowing the standards by which the OSs were judged, it's impossible to say. DOS could be very secure in that it doesn't have attack vectors as you mentioned, but it could also be extremely unsecure as it doesn't have built in protections for the person just walking up and using it.
@mike I guess that's my beef with the author. He never explains why he ranks them the way he does other than user permissions. But legacy systems that are used the way they were originally intended are often more secure because their footprint is smaller and they have specialised uses. For instance, there are decades old mainframes that have never been breached or hacked. But they need to be replaced. Why?
@Limax My understanding why he could rate dos as having the worst security is because dos, 95, 98 and me don't have file permissions. anyone who has physical access to the system essentially can do whatever they want to them, and even remotely in some cases.
@unicornfarts It is a single user system. But I can't see how it could be hacked if it is used the way it was originally intended.
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.