Do they have licenses for any of this stuff? I mean, Id/Bethesda still sells Doom 1, you can't really call these "abandonware" by the normal definition. They're just "really old".
Doom is just the shareware version, just like most of the others (some already called with that fancy modern name "demo"). Some are freeware, some have been released into public domain after they went out of sale.
Is it the full game or the shareware? In another post a few days ago they said it they were only offering shareware versions. Can't check now, I'm on mobile.