QWEEDDYZ: Some content got removed, isn't? Just like Bethesda already did before.
And again. There is few IDs, few bundles (just for one game too). New IDs implemented. And yet GOG+Bethesda failed again keep old items and bring new without issues.
From what I have read, it is my understanding that both games are the Enhanced version, that has been enhanced even more.
I'm not aware of anything being removed, but plenty has been added. I'm not sure how much of the added, is out-of-the-box or needing to be downloaded from Bethesda for free, much like it is with Quake Enhanced, via the game menu.
With Quake Enhanced, you were able to download the additional stuff, and if you wanted, you could back them up as DRM-Free on their own, which is exactly what I did, and placed them in my Quake Enhanced backup folder.
DOOM + DOOM II is a single installer (EXE) file that is just under 900 MB.
Previous Enhanced versions are a combined 631 MB (316 + 315).
FINAL DOOM is not mentioned, so doesn't appear to be included.
Original versions of DOOM and DOOM II are included.