Seth Kenlon from RedHat has been finding old Linux distros from before the war and installed them. How bad is this old shit, from todays POV?
Slackware 1.01 (1993): It does not even have package management. But:
Over all, Slackware 1.01 feels a lot like a fairly modern UNIX—or more appropriately, it feels like modern UNIX might feel to a Linux user. Most everything is familiar, but there are differences here and there. Not nearly as much a difference as you might expect from an operating system released in 1993!
And it continues like that – much of the old stuff works and feels a lot like stuff today. So besides systemd, there has hardly been any progress at all.
For example, some people’s desktop looks like this, even today: