I couldn't run Gamedec Demo out of the box, but managed to make it run after a "xinput1_4,dl" trick. But if it doesn't count I can scratch off this post.

EDIT:

Here is how to actually run Gamedec on Win7 (hint from a developer):

"Game may not launch on Windows 7 due to the missing file "XINPUT1_4.dll". Solution: Go to folder C:\Windows\System32, find file "xinput1_3.dll", copy it to the same folder and rename it as "xinput1_4,dll". After that demo should launch."

Wolfenstein 2 runs on windows 7 as long as you have Vulkan installed on your computer.

Thanks to all! I will update the OP in the next days. Busy atm.

Just wanted to chime in and say, great idea for a thread! :) This will be helpful to me! +1

Do games that can be emulated on Win7 count?
If they do, the post ROM based GOG games compatible with third party emulators thread could be an interesting resource, as long as the user has a way to extract the ROMs (some games come packed in Windows installers, and they could have limitations such as only unpacking on newer versions of Windows).

I think the main purpose of this topic is not to include every game already listed as "W7" compatible on the game page, but rather that GOG have stopped providing accurate information of actual OS requirements of new 2020-2021 games, ie, many new games that are claimed to be "Windows 10 only" will actually run fine on Windows 7. Nearly all 2019 and older (and emulated) games should run on Windows 7 by default.

Riddle of the Sphinx The Awakening (Enhanced Edition) is confirmed to be W10 only. The developer has given up trying to solve a black-screen at startup issue on W7:-

https://steamcommunity.com/app/1521870/discussions/0/3104637814609452202/?ctp=4#c4312743731806252448

Gamedec runs on W7 despite being listed as needing W10.

According to the GOG game forum The Uncertain: Light At The End runs on Windows 7.

https://www.gog.com/forum/the_uncertain/requires_windows_10

I guess my contribution to this thread will dwindle down, as I think my only Windows 7 gaming PC (laptop) is finally dying.

It had some power problems earlier but it seemed to work ok when I bought a replacement power supply, but now "something" has happened to its GPU because either Linux or Windows 7 doesn't recognize it as a NVidia GPU anymore, and the computer runs with "generic" unaccelerated graphics, making it unsuitable for gaming.

My other older (retro-gaming) PCs are running Windows XP, not Windows 7.

Oh well, so long Windows 7...

Not working:

Stubbs the Zombie in Rebel Without a Pulse. Does not work. I tried to do like on this Steam topic: No luck, instacrashes no matter what.

Working:

Gamedec. I reconfirm, not a Windows 10 exclusive: A topic on the forum about it.

In Sound Mind. A go on Windows 7, no errors, no shenanigans. Steam's min reqs confirm. I've no clue why GOG's min differs from.

Little Nightmares II. The workaround of the 1st post is very outdated, no go for the current Enhanced version. What to do? Thanks to Schwertz, here's the instruction how to fix it for.

Special Case
Redout: Space Assault. Yes, it mentions Windows 7, I am aware. The tiny issue with the 1.1.0 version is its shortcut is for Windows 10 (DirectX 12), no fly. One needs to add "-dx11" to fix that.

Sable. Surprisingly, despite no mention anywhere, it works fine on Windows 7. The game itself, of course, needs to be improved.

Severed Steel. It runs on Windows 7, but with an insignificant error message on a startup (it can be closed and all OK). To remove the message forever:
1. Have latest Windows 7 (x64) or install KB4507456 manually;
2. Copy "C:\Windows\System32\CompatTel\api-ms-win-downlevel-kernel32-l2-1-0.dll" and go to your game dir (i.g. "C:\GOG Games\Severed Steel"), then paste it into the "ThankYouVeryCool\Binaries\Win64\" dir;
3. The annoying pop up is no more.

The pop up also occurs for "Comanche," "Gamedec," "Graven," "Mechwarrior 5" and some others. The solution is alike: Put the DLL alongside its prime EXE.

I can confirm that Star Wars Squadrons does not even install on Windows 7 if you have it on Origin. I've seen others say they found a way to play it with some tweaks using ReShade but I'm not aware of any way to even install the game if you have it on Origin.

The Riftbreaker. I removed the block. Afterwards still does not work on at the time of writing, complains on the dxgi.dll and ntdll.dll. Unless someone in the linked topic does find a solution, count it as a game not running on Windows 7.

I bought Panzer Dragoon Remake on Gog and it worked flawlessly on W7. I haven't played the last update though.

Gloomhaven confirmed working on Win7